Liberty User Guide Volume 2
Version Version 2007.03, March 2007
Copyright Notice
© 2004, 2006-2009, 2011-2020 Synopsys, Inc. All rights reserved. This software and documentation contain
confidential and proprietary information that is the property of Synopsys, Inc. The software and documentation are
furnished under a license agreement and may be used or copied only in accordance with the terms of the license
agreement. No part of the software and documentation may be reproduced, transmitted, or translated, in any form or
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Inc., or as expressly provided by the license agreement.
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must assign sequential numbers to all copies. These copies shall contain the following legend on the cover page:
This document is duplicated with the permission of Synopsys, Inc., for the use of Open Source Liberty users.
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All technical data contained in this publication is subject to the export control laws of the United States of America.
Disclosure to nationals of other countries contrary to United States law is prohibited. It is the reader’s responsibility to
determine the applicable regulations and to comply with them.
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SYNOPSYS, INC., AND ITS LICENSORS MAKE NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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and is not responsible for such websites and their practices, including privacy practices, availability, and content.
Synopsys, Inc.
690 E. Middlefield Road
Mountain View, CA 94043
www.synopsys.com
Liberty User Guide Volume 2
Version 2007.03
2
Contents
1. Physical Library Group Description and Syntax . . . . . . . . . . . . . . . . . . . . . . . . . 13
Attributes and Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
phys_library Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
bus_naming_style Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
capacitance_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . 29
capacitance_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
comment Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
current_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 30
current_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
date Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
dist_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
distance_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
frequency_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . .32
frequency_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
has_wire_extension Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
inductance_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 33
inductance_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
is_incremental_library Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
manufacturing_grid Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
power_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . .35
power_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
resistance_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 36
resistance_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
revision Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
SiO2_dielectric_constant Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 37
time_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
time_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
voltage_conversion_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 38
voltage_unit Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
antenna_lut_template Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
resistance_lut_template Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
shrinkage_lut_template Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
spacing_lut_template Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
wire_lut_template Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
2. Specifying Attributes in the resource Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
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Syntax for Attributes in the resource Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
resource Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
contact_layer Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
device_layer Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
overlap_layer Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
substrate_layer Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
3. Specifying Groups in the resource Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Syntax for Groups in the resource Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
array Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
floorplan Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
cont_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
corner_min_spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
max_stack_level Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
enclosed_cut_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
implant_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
min_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
spacing_from_layer Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
ndiff_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
pdiff_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
poly_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
avg_lateral_oxide_permittivity Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 80
avg_lateral_oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . 81
height Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
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oxide_permittivity Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
res_per_sq Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
shrinkage Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
conformal_lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 84
lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
routing_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
avg_lateral_oxide_permittivity Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 90
avg_lateral_oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . 91
baseline_temperature Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
cap_multiplier Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
cap_per_sq Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
coupling_cap Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
default_routing_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
edgecapacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
field_oxide_permittivity Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
field_oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
fill_active_spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
fringe_cap Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
height Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
inductance_per_dist Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
max_current_density Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
max_length Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
max_observed_spacing_ratio_for_lpe Simple Attribute . . . . . . . . . . . . . . . . 98
max_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
min_area Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
min_enclosed_area Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
min_enclosed_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
min_fat_wire_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
min_fat_via_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
min_length Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
min_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102
min_wire_split_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
offset Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
oxide_permittivity Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
pitch Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
process_scale_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
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res_per_sq Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
res_temperature_coefficient Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 106
routing_direction Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
same_net_min_spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 107
shrinkage Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
u_shaped_wire_spacing Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 109
wire_extension Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
wire_extension_range_check_connect_only Simple Attribute . . . . . . . . . . 110
wire_extension_range_check_corner Simple Attribute . . . . . . . . . . . . . . . 110
conformal_lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . 111
lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
min_extension_width Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 112
min_shape_edge Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
plate_cap Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
ranged_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
spacing_check_style Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . .114
stub_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
end_of_line_spacing_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
extension_via_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
min_edge_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125
min_enclosed_area_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
notch_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
resistance_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
shrinkage_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
spacing_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
wire_extension_range_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
routing_wire_model Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
wire_length_x Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
wire_length_y Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
adjacent_wire_ratio Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
overlap_wire_ratio Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
wire_ratio_x Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
wire_ratio_y Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
site Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
on_tile Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
site_class Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
symmetry Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
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size Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
tile Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
tile_class Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
size Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
via Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
capacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
inductance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
is_default Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
is_fat_via Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
resistance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
res_temperature_coefficient Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 148
top_of_stack_only Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
via_id Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
foreign Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
via_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
via_array_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
4. Specifying Attributes in the topological_design_rules Group . . . . . . . . . . . . . 161
Syntax for Attributes in the topological_design_rules Group . . . . . . . . . . . . . . . . . 161
topological_design_rules Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
antenna_inout_threshold Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 162
antenna_input_threshold Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 162
antenna_output_threshold Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . 163
min_enclosed_area_table_surrounding_metal Simple Attribute . . . . . . . . 163
contact_min_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 164
corner_min_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
end_of_line_enclosure Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . 165
min_enclosure Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
diff_net_min_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 166
min_generated_via_size Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . .166
min_overhang Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167
same_net_min_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . 167
5. Specifying Groups in the topological_design_rules Group . . . . . . . . . . . . . . . 169
Syntax for Groups in the topological_design_rules Group . . . . . . . . . . . . . . . . . . . 169
antenna_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
adjusted_gate_area_calculation_method Simple Attribute . . . . . . . . . . . . 170
adjusted_metal_area_calculation_method Simple Attribute . . . . . . . . . . . .171
antenna_accumulation_calculation_method Simple Attribute . . . . . . . . . . 171
antenna_ratio_calculation_method Simple Attribute . . . . . . . . . . . . . . . . . 172
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apply_to Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
geometry_calculation_method Simple Attribute . . . . . . . . . . . . . . . . . . . . . 172
metal_area_scaling_factor_calculation_method Simple Attribute . . . . . . . 173
pin_calculation_method Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 174
routing_layer_calculation_method Simple Attribute . . . . . . . . . . . . . . . . . . 174
layer_antenna_factor Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 175
adjusted_gate_area Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175
adjusted_metal_area Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
antenna_ratio Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177
metal_area_scaling_factor Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
default_via_generate Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
density_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
extension_wire_spacing_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183
extension_wire_qualifier Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
min_total_projection_length_qualifier Group . . . . . . . . . . . . . . . . . . . . . . . 185
spacing_check_qualifier Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
stack_via_max_current Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
bottom_routing_layer Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
top_routing_layer Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
max_current_ac_absavg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
max_current_ac_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
max_current_ac_peak Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
max_current_ac_rms Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
max_current_dc_avg Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
via_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
via_list Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
routing_layer_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
via_rule_generate Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
capacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
inductance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
resistance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
res_temperature_coefficient Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 201
contact_formula Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
routing_formula Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
wire_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
layer_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210
via Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
wire_slotting_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
max_metal_density Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
min_length Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
min_width Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222
slot_length_range Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
slot_length_side_clearance Complex Attribute . . . . . . . . . . . . . . . . . . . . . 223
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slot_length_wise_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . .224
slot_width_range Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
slot_width_side_clearance Complex Attribute . . . . . . . . . . . . . . . . . . . . . . 224
slot_width_wise_spacing Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . 225
6. Specifying Attributes and Groups in the process_resource Group . . . . . . . . .226
Syntax for Attributes in the process_resource Group . . . . . . . . . . . . . . . . . . . . . . . 226
baseline_temperature Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226
field_oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
process_scale_factor Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
plate_cap Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228
Syntax for Groups in the process_resource Group . . . . . . . . . . . . . . . . . . . . . . . . 229
process_cont_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
process_routing_layer Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
cap_multiplier Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230
cap_per_sq Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
coupling_cap Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
edgecapacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
fringe_cap Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
height Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
inductance_per_dist Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233
lateral_oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . 234
oxide_thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
res_per_sq Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235
shrinkage Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
thickness Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
conformal_lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . 236
lateral_oxide Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
resistance_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
shrinkage_table Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
process_via Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
capacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
inductance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
resistance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
res_temperature_coefficient Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 241
process_via_rule_generate Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
capacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
inductance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
resistance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
res_temperature_coefficient Simple Attribute . . . . . . . . . . . . . . . . . . . . . . 244
process_wire_rule Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
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process_via Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
7. Specifying Attributes and Groups in the macro Group . . . . . . . . . . . . . . . . . . 248
macro Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
cell_type Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
create_full_pin_geometry Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
eq_cell Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
extract_via_region_within_pin_area Simple Attribute . . . . . . . . . . . . . . . . . . . . 251
in_site Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
in_tile Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
leq_cell Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
source Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
symmetry Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
extract_via_region_from_cont_layer Complex Attribute . . . . . . . . . . . . . . . . . . 255
obs_clip_box Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
origin Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
size Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
foreign Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
orientation Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
origin Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258
obs Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
via Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
via_iterate Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
geometry Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
site_array Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
orientation Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
iterate Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
origin Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271
8. Specifying Attributes and Groups in the pin Group . . . . . . . . . . . . . . . . . . . . . 272
pin Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272
capacitance Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
direction Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
eq_pin Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
must_join Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
pin_shape Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .275
pin_type Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
antenna_contact_accum_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . 276
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antenna_contact_accum_side_area Complex Attribute . . . . . . . . . . . . . . . . . . 276
antenna_contact_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
antenna_contact_area_partial_ratio Complex Attribute . . . . . . . . . . . . . . . . . . 278
antenna_contact_side_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . 278
antenna_contact_side_area_partial_ratio Complex Attribute . . . . . . . . . . . . . . 279
antenna_diffusion_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . .279
antenna_gate_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
antenna_metal_accum_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . .280
antenna_metal_accum_side_area Complex Attribute . . . . . . . . . . . . . . . . . . . 281
antenna_metal_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
antenna_metal_area_partial_ratio Complex Attribute . . . . . . . . . . . . . . . . . . . .282
antenna_metal_side_area Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . .282
antenna_metal_side_area_partial_ratio Complex Attribute . . . . . . . . . . . . . . . 283
foreign Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
orientation Simple Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
origin Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .285
port Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .285
via Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
via_iterate Complex Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
geometry Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
9. Developing a Physical Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .294
Creating the Physical Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Naming the Source File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Naming the Physical Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .294
Defining the Units of Measure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
10. Defining the Process and Design Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Defining the Technology Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Defining the Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Defining the Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .298
Contact Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298
Overlap Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298
Routing Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Specifying Net Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
Device Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Defining Vias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .302
Naming the Via . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .302
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Defining the Via Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
Defining the Geometry for Simple Vias . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Defining the Geometry for Special Vias . . . . . . . . . . . . . . . . . . . . . . . . . . .304
Referencing a Foreign Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Defining the Placement Sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Standard Cell Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Gate Array Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .308
11. Defining the Design Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Defining the Design Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Defining Minimum Via Spacing Rules in the Same Net . . . . . . . . . . . . . . . . . . 313
Defining Same-Net Minimum Wire Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Defining Same-Net Stacking Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Defining Nondefault Rules for Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Defining Rules for Selecting Vias for Special Wiring . . . . . . . . . . . . . . . . . . . . 316
Defining Rules for Generating Vias for Special Wiring . . . . . . . . . . . . . . . . . . .318
Defining the Generated Via Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
A. Parasitic RC Estimation in the Physical Library . . . . . . . . . . . . . . . . . . . . . . . . 321
Modeling Parasitic RC Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .321
Variables Used in Parasitic RC Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . .322
Variables for Routing Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Variables for Estimated Routing Wire Model . . . . . . . . . . . . . . . . . . . . . . . 323
Equations for Parasitic RC Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Capacitance per Unit Length for a Layer . . . . . . . . . . . . . . . . . . . . . . . . . .324
Resistance and Capacitance for Each Routing Direction . . . . . . . . . . . . . 325
.plib Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
12
1
Physical Library Group Description and Syntax
This chapter describes the role of the phys_library group in defining a physical library.attributessee attributes, physical libraryattributessee attributes, pseudo-physical library
The information in this chapter includes a description and syntax example for the attributes
that you can define within the phys_library group.
Attributes and Groups
The phys_library group is the superior group in the physical library. The phys_library
group contains all the groups and attributes that define the physical library.
Example 1 lists the attributes and groups that you can define within a physical library.
The following chapters include descriptions and syntax examples for the groups that you
can define within the phys_library group.
Example 1 Syntax for the Attributes and Groups in the Physical Library
phys_library(library_name
id
) {
bus_naming_style: string ;
capacitance_conversion_factor : integer ;
capacitance_unit : 1pf | 1ff | 10ff | 100ff ;
comment : string ;
current_conversion_factor : integer ;
current_unit : 100uA | 100mA | 1A | 1uA | 10uA | 1mA | 10mA ;
date : string ;
dist_conversion_factor : integer ;
distance_unit : 1mm | 1um ;
frequency_conversion_factor : integer ;
frequency_unit : 1mhz ;
gds2_conversion_factor : integer ;
has_wire_extension: Boolean ;
inductance_conversion_factor : integer ;
inductance_unit : 1fh | 1ph | 1nh | 1uh | 1mh | 1h ;
is_incremental_library : Boolean ;
manufacturing_grid : float ;
power_conversion_factor : integer ;
power_unit : 1uw | 10uw | 100uw | 1mw | 10mw | 100mw | 1w ;
resistance_conversion_factor : integer ;
resistance_unit : 1ohm | 100ohm | 10ohm | 1kohm ;
revision : string ;
Si02_dielectric_constant : float ;
time_conversion_factor : integer ;
time_unit : 1ns | 100 ps | 10ps | 1ps ;
voltage_conversion_factor : integer ;
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voltage_unit : 1mv | 10mv | 100mv | 1v ;
antenna_lut_template (template_name
id
) {
variable_1 : antenna_diffusion_area ;
index_1("float, float, float, ...") ;
} /* end antenna_lut_template */
resistance_lut_template (template_name
id
) {
variable_1: routing_width | routing_spacing ;
variable_2: routing_width | routing_spacing ;
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
} /* end resistance_lut_template */
shrinkage_lut_template (template_name
id
) {
variable_1: routing_width | routing_spacing ;
variable_2: routing_width | routing_spacing ;
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
} /* end shrinkage_lut_template */
spacing_lut_template (template_name
id
) {
variable_1: routing_width ;
variable_2: routing_width ; routing_length ;
variable_3: routing_length ;
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
} /* end *spacing_lut_template */
wire_lut_template (template_name
id
) {
variable_1: extension_width |extension_length | bottom_routing_width |
top_routing_width |routing_spacing | routing_width ;
variable_2: extension_width |extension_length | bottom_routing_width |
top_routing_width |routing_spacing | routing_width ;
variable_3: extension_width |extension_length | routing_spacing |
routing_width ;
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
} /* end wire_lut_template */
resource(architecture
enum
) {
contact_layer(layer_name
id
) ;
device_layer(layer_name
id
) ;
overlap_layer(layer_name
id
) ;
substrate_layer(layer_name
id
) ;
cont_layer (layer_name
id
) {
corner_min_spacing : float ;
max_current_density ;float ;
max_stack_level ;integer ;
spacing : float ;
enclosed_cut_rule () {
max_cuts : integer ;
max_neighbor_cut_spacing : float ;
min_cuts : integer ;
min_enclosed_cut_spacing : float ;
min_neighbor_cut_spacing : float ;
} /* end enclosed_cut_rule */
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
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index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
} /* end cont_layer */
extension_via_rule () {
related_layer : name
id
;
min_cuts_table ( wire_lut_template_name ) {
index_1
index_2
values
} * end min_cuts_table */
reference_cut_table ( via_array_lut_template_name ) {
index_1
index_2
values
} /* end reference_cut_table */
} /* end extension_via_rule */
implant_layer () {
min_width : float ;
spacing ; float ;
spacing_from_layer (float, layer_name
id
) ;
} /* end implant_layer */
ndiff_layer () {
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
index_1 ("float, float, float, ...") ;
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index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
} /*end ndiff_layer */
pdiff_layer () {
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
} /*end pdiff_layer */
poly_layer(layer_name
id
)) {
avg_lateral_oxide_permittivity : float ;
avg_lateral_oxide_thickness : float ;
conformal_lateral_oxide (thickness
float
, topwall_thickness
float
,
sidewall_thickness
float
, permittivity
float
) ;
height : float ;
lateral_oxide : (thickness
float
, permittivity
float
) ;
oxide_permittivity : float ;
oxide_thickness : float ;
res_per_sq : float ;
shrinkage : float ;
thickness : float ;
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
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index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
} /* end poly_layer */
routing_layer(layer_name
id
)) {
avg_lateral_oxide_permittivity
avg_lateral_oxide_thickness
baseline_temperature : float ;
cap_multiplier : float ;
cap_per_sq : float ;
conformal_lateral_oxide (thickness
float
, topwall_thickness
float
,
sidewall_thickness
float
, permittivity
float
) ;
coupling_cap : float ;
default_routing_width : float ;
edgecapacitance : float ;
field_oxide_permittivity : float ;
field_oxide_thickness : float ;
fill_active_spacing : float ;
fringe_cap : float ;
height : float ;
inductance_per_dist : float ;
lateral_oxide : (thickness
float
, permittivity
float
) ;
max_current_density : float ;
max_length : float ;
max_observed_spacing_ratio_for_lpe : float ;
max_width : float ;
min_area : float ;
min_enclosed_area : float ;
min_enclosed_width : float ;
min_extension_width ; ;
min_fat_wire_width : float ;
min_fat_via_width : float ;
min_length : float ;
min_shape_edge (float, integer, Boolean ) ;
min_width : float ;
min_wire_split_width : float ;
offset : float ;
oxide_permittivity : float ;
oxide_thickness : float ;
pitch : float ;
plate_cap(float, ..., float) ;
process_scale_factor : float ;
ranged_spacing(float, float, float) ;
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res_per_sq : float ;
res_temperature_coefficient : float ;
routing_direction : vertical | horizontal ;
same_net_min_spacing : float ;
shrinkage : float ;
spacing : float ;
spacing_check_style : manhattan | diagonal ;
stub_spacing (spacing
float
, max_length_threshold
float
);
thickness : float ;
u_shaped_wire_spacing : float ;
wire_extension : float ;
wire_extension_range_check_connect_only : Boolean ;
wire_extension_range_check_connect_corner : Boolean ;
array(array_name) {
floorplan(floorplan_name
id
) {
/* floorplan_name is optional */
/* when omitted, results in default floorplan */
site_array(site_name
id
) {
iterate(num_x
int
, num_y
int
, spacing_x
float
,
spacing_y
float
) ;
orientation : FE | FN | E | FS | FW | N | S | W ;
origin(x
float
, y
float
) ;
placement_rule : regular | can_place | cannot_occupy ;
} /* end site_array */
} /* end floorplan */
routing_grid () {
grid_pattern (float, integer, float) ;
routing_direction : horizontal | vertical ;
} /* end routing_grid */
tracks() {
layers : "layer1_name
id
, ..., layern_name
id
" ;
routing_direction : horizontal | vertical ;
track_pattern(float, integer, float) ;
/* starting coordinate, number, spacing */
} /*end tracks */
} /* end array */
end_of_line_spacing_rule () {
end_of_line_corner_keepout_width : float ;
end_of_line_edge_checking : value
enum
;
end_of_line_metal_max_width : float ;
end_of_line_min_spacing : float ;
}
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
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index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
min_edge_rule () {
concave_corner_required : Boolean ;
max_number_of_min_edges : value
int
;
max_total_edge_length : float ;
min_edge_length : float ;
}
min_enclosed_area_table () {
index_1 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
notch_rule () {
min_notch_edge_length : float ;
min_notch_width : float ;
min_wire_width : float ;
}
resistance_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end resistance_table */
shrinkage_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end shrinkage_table */
spacing_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end spacing_table */
wire_extension_range_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end wire_extension_range_table */
} /* end routing_layer */
routing_wire_model(model_name
id
) {
adjacent_wire_ratio(float, ..., float) ;
overlap_wire_ratio(float, ..., float) ;
wire_length_x(float) ;
wire_length_y(float) ;
wire_ratio_x(float, ..., float) ;
wire_ratio_y(float, ..., float) ;
} /* end routing_wire_model */
site(site_name
id
) {
on_tile : value
id
;
site_class : pad | core ; /* default = core */
size(size_x
float
, size_y
float
) ;
symmetry : x | y | r | xy | rxy ; /* default = none */
} /* end site */
tile (tile name) {
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size (float, float) ;
tile_class : pad | core ; /* default = core */
}
via(via_name
id
) {
capacitance : float ;
inductance : float ;
is_default : Boolean ;
is_fat_via : Boolean ;
res_temperature_coefficient : float ;
resistance : float ; /* per contact-cut rectangle */
same_net_min_spacing(layer_name
id
, layer_name
id
, spacing_value
float
,
is_stack
Boolean
) ;
top_of_stack_only : Boolean ;
via_id : value
int
;
foreign(foreign_object_name
id
) {
orientation : FE | FN | E | FS | FW | N | S | W ;
origin(x
float
, y
float
) ;
} /* end foreign */
via_layer(layer_name
id
) {
contact_array_spacing ( float, float ) ;
contact_spacing ( float, float ) ;
enclosure ( float, float ) ;
max_cuts ( value
int
, value
int
) ;
max_wire_width : float ;
min_cuts ( integer , integer ) ;
min_wire_width ; float ;
rectangle(X0
float
, Y0
float
, X1
float
, Y1
float
) ;
/* 1 or more rectangle attributes allowed */ ;
rectangle_iterate ( value
int
, value
int
, float, float, float,
float,float,float ) ;
} /* end via_layer */
} /* end via */
via_array_rule () {
min_cuts_table ( via_array_lut_template_name ) {
index_1
index_2
values
} * end min_cuts_table */
reference_cut_table ( via_array_lut_template_name ) {
index_1
index_2
values
} /* end reference_cut_table */
} /* end via_array_rules */
} /*end resource */
topological_design_rules() {
antenna_inout_threshold : float ;
antenna_input_threshold : float ;
antenna_output_threshold : float ;
contact_min_spacing(layer_name
id
, layer_name
id
, float) ;
corner_min_spacing (value
id
, value
id
, float ) ;
diff_net_min_spacing (value
id
, value
id
, float ) ;
end_of_line_enclosure (value
id
, value
id
, float ) ;
min_enclosure (value
id
, value
id
, float ) ;
min_enclosed_area_table_surrounding_metal : value
enum
;
min_generated_via_size(float, float) ; /* x, y */
min_overhang (layer1
string
, layer2
string
, spacing_value
float
) ;
same_net_min_spacing(layer_name
id
, layer_name
id
, spacing_value
float
,
is_stack
Boolean
) ;
antenna_rule (antenna_rule_name
id
) {
adjusted_gate_area_calculation_method () ;
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adjusted_metal_area_calculation_method () ;
antenna_accumulation_calculation_method () ;
antenna_ratio_calculation_method () ;
apply_to : gate_area | gate_perimeter | diffusion_area ;
geometry_calculation_method : all_geometries | connected_only ;
layer_antenna_factor (layer_name
string
, antenna_factor
float
) ;
metal_area_scaling_factor_calculation_method : value
enum
;
pin_calculation_method : all_pins | each_pin ;
routing_layer_calculation_method : side_wall_area | top_area |
side_wall_and_top_area | segment_length | segment_perimeter ;
adjusted_gate_area () {
index_1
values
}
adjusted_metal_area () {
index_1
values
}
antenna_ratio (template_name
id
) {
index_1 (float,float,float,...)
values (float,float,float,...)
}
metal_area_scaling_factor () {
index_1 (float,float,float,...)
values (float,float,float,...)
}
} /* end antenna_rule */
default_via_generate () {
via_routing_layer() {}
via_contact_layer () {}
}
density_rule () {
check_window_size () ;
check_step : ;
density_range () ;
}
extension_wire_spacing_rule () {
extension_wire_qualifier () {
connected_to_fat_wire : Boolean ;
corner_wire : Boolean ;
not_connected_to_fat_wire : Boolean ;
} /* end extension_wire_spacing_rule */
min_total_projection_length_qualifier () {
non_overlapping_projection : Boolean ;
overlapping_projection : Boolean ;
parallel_length : Boolean ;
} /* end min_total_projection_length_qualifier */
spacing_check_qualifier () {
corner_to_corner : Boolean ;
non_overlapping_projection_wires : Boolean ;
overlapping_projection_wires : Boolean ;
wires_to_check : value
enum
;
} /* end spacing_check_qualifier */
} /* end extension_wire_spacing_rule */
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stack_via_max_current () {
bottom_routing_layer : routing_layer_name
id
;
top_routing_layer : routing_layer_name
id
;
max_current_ac_absavg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_peak (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_ac_rms (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
index_3 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
max_current_dc_avg (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
}
} /* end stack_via_max_current */
via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) { /* 2 or more */
contact_overhang : float ;
max_wire_width : float ;
metal_overhang : float ;
min_wire_width : float ;
routing_direction : horizontal | vertical ;
via_list : ;
} /* end routing_layer_rule */
vias : "via_name1
id
, ...,via_nameN
id
," ;
} /* end via_rule */
via_rule_generate(via_rule_generate_name
id
) {
capacitance : float ;
inductance : float ;
res_temperature_coefficient : float ;
resistance : float ;
routing_formula(layer_name
id
) {
contact_overhang : float ;
enclosure ( float, float );
max_wire_width : float ;
metal_overhang : float ;
min_wire_width : float ;
routing_direction : horizontal | vertical ;
} /* end routing_formula */
contact_formula(layer_name
id
) {
contact_array_spacing ( float, float ) ;
contact_spacing(X
float
, Y
float
) ;
max_cuts ( value
int
, value
int
) ;
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max_cut_rows_current_direction : float ;
min_number_of_cuts : float ;
rectangle(X0
float
, Y0
float
, X1
float
, Y1
float
) ;
resistance : float ;
routing_direction : value
enum
;
} /* end contact_formula */
} /* end via_rule_generate */
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
capacitance : float ;
inductance : float ;
res_temperature_coefficient : float ;
resistance : float ;
same_net_min_spacing(layer_name
id
, layer_name
id
, spacing_value
float
,
is_stack
Boolean
) ;
foreign(foreign_object_name
id
) {
orientation : FE | FN | E | FS | FW | N | S | W ;
origin(float, float) ;
} /* end foreign */
via_layer(layer_name
id
) {
contact_array_spacing ( float, float ) ;
enclosure ( float, float ) ;
max_cuts ( value
int
, value
int
) ;
rectangle(X0
float
, Y0
float
, X1
float
, Y1
float
) ;
/* 1 or more rectangles */
} /* end via_layer */
} /* end via */
layer_rule(layer_name
id
) {
min_spacing : float ;
same_net_min_spacing(layer_name
id
, layer_name
id
, spacing_value
float
,
is_stack
Boolean
) ;
/* layer1, layer2, spacing, is_stack */
wire_extension : float ;
wire_width : float ;
} /* end layer_rule */
} /* end wire_rule */
wire_slotting_rule (wire_slotting_rule_name
id
) {
max_metal_density : float ;
min_length : float ;
min_width : float ;
slot_length_range (min
float
, max
float
) ;
slot_length_side_clearance (min
float
, max
float
) ;
slot_length_wise_spacing (min
float
, max
float
) ;
slot_width_range (min
float
, max
float
) ;
slot_width_side_clearance (min
float
, max
float
) ;
slot_width_wise_spacing (min
float
, max
float
) ;
} /* end wire_slotting_rule */
} /* end topological_design_rule */
process_resource(process_name
id
{
baseline_temperature : float ;
field_oxide_thickness : float ;
plate_cap(float, ..., float) ;
process_scale_factor : float ;
process_cont_layer () {
process_routing_layer(layer_name
id
) {
cap_multiplier : float ;
cap_per_sq : float ;
conformal_lateral_oxide (thickness
float
, topwall_thickness
float
,
sidewall_thickness
float
, permittivity
float
) ;
coupling_cap : float ;
edgecapacitance : float ;
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fringe_cap : float ;
height : float ;
inductance_per_dist : float ;
lateral_oxide (thickness
float
, permittivity
float
) ;
lateral_oxide_thickness : float ;
oxide_thickness : float ;
res_per_sq : float ;
shrinkage : float ;
thickness : float ;
resistance_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end resistance_table */
shrinkage_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") ;
} /* end shrinkage_table */
} /* end process_routing_layer */
process_via(via_name
id
) {
capacitance : float ;
inductance : float ;
res_temperature_coefficient : float ;
resistance : float ; /* per contact-cut rectangle */
} /* end process_via */
process_via_rule_generate(via_name
id
) {
capacitance : float ;
inductance : float ;
res_temperature_coefficient : float ;
resistance : float ;
} /* end process_via_rule_generate */
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
capacitance : float ;
inductance : float ;
res_temperature_coefficient : float ;
resistance : float ;
} /* end process_via */
} /* end process_wire_rule */
} /*end process_resource */
visual_settings () {
stipple (stipple_name
id
) {
height : integer ;
width : integer ;
pattern (value_1
enum
, ..., value_N
enum
;
} /* end stipple */
primary_color () {
light_blue : integer ;
light_green : integer ;
light_red : integer ;
medium_blue : integer ;
medium_green : integer ;
medium_red : integer ;
} /* end primary color */
color (color_name
id
) {
blue_intensity : integer ;
green_intensity : integer ;
red_intensity : integer ;
} /* end color */
height : integer ;
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line_style (line_name
id
) {
pattern (value_1
enum
, ..., value_N
enum
;
width : integer ;
} /* end line_styles */
} /* end visual settings */
layer_panel () {
display_layer (display_layer_name
id
) {
blink : Boolean ;
color : color_name
string
;
is_mask_layer : Boolean ;
line_style : line_style_name
string
;
mask_layer : layer_name
string
;
stipple : stipple_name
string
;
selectable : Boolean ;
visible : Boolean ;
} /* end display_layer */
} /* end layer_panel */
milkyway_layer_map () {
stream_layer (layer_name
id
) {
gds_map (layer
int
, datatype
int
) ;
mw_map (layer
int
, datatype
int
) ;
net_type : power | ground | clock | signal | viabot | viatop ;
object_type : data | text | data_text ;
} /* end stream_layer */
} /* end milkyway_layer_map */
pr_preparation_rules() {
pr_view_extraction_rules() {
apply_to_cell_type : value
enum
;
generate_cell_boundary : Boolean ;
blockage_extraction() {
max_dist_to_combine_blockage (“value
string
, value
float
”);
preserve_all_metal_blockage : Boolean ;
routing_blockage_display : Boolean ;
routing_blockage_includes_spacing : Boolean ;
treat_all_layers_as_thin_wires ; Boolean ;
treat_layer_as_thin_wire (value
string
, value
string
, ... ) ;
}
pin_extraction () {
expand_small_pin_on_blockage : Boolean ;
extract_connectivity : Boolean ;
extract_connectivity_thru_cont_layers(value
string
,value
string
, ... );
/* these three attributes can have multiple pair-statements */
must_conn_area_layer_map ( “value
string
, value
string
”);
must_conn_area_min_width (“value
string
, value
float
”);
pin2text_layer_map (value
string
, value
string
) ;
}
via_region_extraction () {
apply_to_vias (via_name
string
, via_name
string
, ... ) ;
apply to_macro : Boolean ;
use_rotated_vias : Boolean ;
top_routing_layer : value
string
;
}
}
cell_flatten_rules() {
save_flattened_data_to_original : Boolean ;
}
pr_boundary_generation_rules () {
pr_boundary_generation () {
bottom_boundary_offset : value
float
;
bottom_boundary_reference : value
enum
;
doubleback_pg_row : Boolean ;
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left_boundary_offset : value
float
;
left_boundary_reference : value
enum
;
on_overlap_layer : Boolean ;
use_overlap_layer_as_boundary
}
tile_generation () {
all_cells_single_height : Boolean ;
pg_rail_orientation : value
enum
;
tile_name : value
id
;
tile_height : value
float
;
tile_width : value
floaat
;
}
}
streamin_rules () {
boundary_layer_map ( value
int
, value
int
) ;
overwrite_existing_cell : Boolean ;
save_unmapped_mw_layers : Boolean ;
save_unmapped_stream_layers : Boolean ;
text_scaling_factor : value
float
;
update_existing_cell : Boolean ;
use_boundary_layer_as_geometry : Boolean ;
}
}
macro(cell_name
id
) {
cell_type : cover | bump_cover | ring | block | blackbox_block | pad |
areaio_pad | input pad | output_pad | inout_pad |
power_pad | spacer_pad | core | antennadiode_core |
feedthru_core | spacer_core | tiehigh_core | tielow_core
| pre_endcap | post_endcap | topleft_endcap |
topright_endcap | bottomleft_endcap |
bottomright_endcap ;
create_full_pin_geometry : Boolean; /* default TRUE */
eq_cell : eq_cell_name
id
;
extract_via_region_from_cont_layer (string, string, ...) ;
extract_via_region_within_pin_area : Boolean ;
in_site : site_name
id
;
in_tile : tile_name
id
;
leq_cell : leq_cell_name
id
;
obs_clip_box(float, float, float, float); /* top, right, bottom, left */
origin(float, float) ;
source : user | generate | block ;
size(float, float) ;
symmetry : x | y | xy | r | rxy ; /* default = none */
foreign(foreign_object_name
id
) {
orientation : FE | FN | E | FS | FW | N | S | W ;
origin(float, float) ;
} /* end foreign */
obs() {
via(via_name
id
, x
float
, y
float
) ;
via_iterate(int, int, float, float, string, float, float) ;
/* num_x, num_y, spacing_x, spacing_y, via_name
id
, start_x, start_y */
geometry(layer_name
id
) {
core_blockage_margin : value
float
;
feedthru_area_layer : value
string
;
generate_core_blockage : Boolean ;
max_dist_to_combine_current_layer_blockage( value
float
, value
float
) ;
path(float, float, float, ...) ;
/* width, numX, numY, spaceX, spaceY, width, x0, y0, x1, y1, ... */
path_iterate(integer, integer, float, float, ...) ;
/* width, numX, numY, spaceX, spaceY, width, x0, y0, x1, y1, ... */
polygon(float, float, float, float, float, float, ...) ;
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/* x, y, x0, y0, x1, x2, ..., */
polygon_iterate(integer, integer, float, float, float, float,
float, float, ...) ;
/* numX, numY, spaceX, spaceY, x0, y0, x1, y1, ... */
preserve_current_layer_blockage : Boolean ;
treat_current_layer_as_thin_wires : Boolean ;
rectangle(X0
float
, Y0
float
, X1
float
, Y1
float
) ;
rectangle_iterate(integer, integer, float, float, float, float,
float, float) ;
/* numX, numY, spaceX, spaceY, x0, y0, x1, y1 */
treat_current_layer_as_thin_wire : Boolean ;
} /* end geometry */
} /* end obs */
pin(pin_name
id
) {
antenna_contact_accum_area (float, float, float, ...) ;
antenna_contact_accum_side_area (float, float, float, ...) ;
antenna_contact_area (float, float, float, ...) ;
antenna_contact_area_partial_ratio (float, float, float, ...) ;
antenna_contact_side_area (float, float, float, ...) ;
antenna_contact_side_area_partial_ratio (float, float, float, ...) ;
antenna_diffusion_area (float, float, float, ...) ;
antenna_gate_area (float, float, float, ...) ;
antenna_metal_accum_area (float, float, float, ...) ;
antenna_metal_accum_side_area (float, float, float, ...) ;
antenna_metal_area (float, float, float, ...) ;
antenna_metal_area_partial_ratio (float, float, float, ...) ;
antenna_metal_side_area (float, float, float, ...) ;
antenna_metal_side_area_partial_ratio (float, float, float, ...) ;
capacitance : float ;
direction : inout | input | feedthru | output | tristate ;
eq_pin : pin_name
id
;
must_join : pin_name
id
;
pin_shape : clock | power | signal | analog | ground ;
pin_type : clock | power | signal | analog | ground ;
foreign(foreign_object_name
id
) {
orientation : FE | FN | E | FS | FW | N | S | W ;
origin(x
float
, y
float
) ;
} /* end foreign */
port() {
via(via_name
id
, float, float) ;
via_iterate(integer, integer, float, float, string, float, float) ;
/*num_x, num_y, spacing_x, spacing_y, via_name
id
, start_x, start_y */
geometry(layer_name
id
) {
path(float, float, float, ...) ;
/* width, numX, numY, spaceX, spaceY, width, x0, y0, x1, y1, ... */
path_iterate(integer, integer, float, float, float, float,...) ;
/* width, numX, numY, spaceX, spaceY, width, x0, y0, x1, y1, ... */
polygon(float, float, float, float, float, float, ...) ;
/* x, y, x0, y0, x1, x2, ..., */
polygon_iterate(integer, integer, float, float, ...) ;
/* numX, numY, spaceX, spaceY, x0, y0, x1, y1, ... */
rectangle(X0
float
, Y0
float
, X1
float
, Y1
float
) ;
/* numX, numY, spaceX, spaceY, x0, y0, x1, y1 */
rectangle_iterate(integer, integer, float, float, float, float,
float, float) ;
/* numX, numY, spaceX, spaceY, x0, y0, x1, y1 */
} /* end geometry */
} /* end port */
} /* end pin */
site_array(site_name
id
) {
orientation : FE | FN | E | FS | FW | N | S | W ;
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origin(x
float
, y
float
) ;
iterate(num_x
int
, num_y
int
, spacing_x
float
, spacing_y
float
);
} /* end site_array */
} /* end macro */
} /* end phys_library */
phys_library Group
The first line in the phys_library group names the library. This line is the first executable
statement in your library.
Syntax
phys_library (library_name
id
) {
... library description ...
}
library_name
The name of your physical library.
Example
phys_library(sample) {
...library description...
}
bus_naming_style Simple Attribute
Defines a naming convention for bus pins.
Syntax
phys_library(library_name
id
) {
... bus_naming_style :"value
string
";
...
}
value
Can contain alphanumeric characters, braces, underscores, dashes, or
parentheses. Must contain one %s symbol and one %d symbol. The %s and %d
symbols can appear in any order, but at least one nonnumeric character must
separate them. bus_naming_style attributecharacters in bus_naming_style attributesymbols in
The colon character is not allowed in a bus_naming_style attribute value
because the colon is used to denote a range of bus members.
You construct a complete bused-pin name by using the name of the owning bus
and the member number. The owning bus name is substituted for the %s, and
the member number replaces the %d.
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Example
bus_naming_style : "%s[%d]" ;
capacitance_conversion_factor Simple Attribute
The capacitance_conversion_factor attribute specifies the capacitance resolution
in the physical library database. For example, when you specify a value of 1000, all the
capacitance values are stored in the database as 1/1000 of the capacitance_unit value.
Syntax
phys_library(library_name
id
) {
...
capacitance_conversion_factor : value
int
;
...
}
value
Valid values are any multiple of 10.
Example
capacitance_conversion_factor : 1000 ;
capacitance_unit Simple Attribute
The capacitance_unit attribute specifies the unit for capacitance.
Syntax
phys_library(library_name
id
) {
...
capacitance_unit : value
enum
;
...
}
value
Valid values are 1pf, 1ff, 10ff, 100ff, 1nf, 1uf, 1mf, and 1f.
Example
capacitance_unit : 1pf ;
comment Simple Attribute
This optional attribute lets you provide additional descriptive information about the library.
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Syntax
phys_library(library_name
id
) {
comment : "value
string
" ;
...
}
value
Any alphanumeric sequence.
Example
comment : "0.18 CMOS library for SNPS" ;
current_conversion_factor Simple Attribute
The current_conversion_factor attribute specifies the current resolution in the physical
library database. For example, when you specify a value of 1000, all the current values are
stored in the database as 1/1000 of the current_unit value.
Syntax
phys_library(library_name
id
) {
...
current_conversion_factor : value
int
;
...
}
value
Valid values are any multiple of 10.
Example
current_conversion_factor : 1000 ;
current_unit Simple Attribute
The current_unit attribute specifies the unit for current.
Syntax
phys_library(library_name
id
) {
...
current_unit : value
enum
;
...
}
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value
Valid values are 1uA, 1mA, and 1A.
Example
current_unit : 1mA ;
date Simple Attribute
The date attribute specifies the library creation date.
Syntax
phys_library(library_name
id
) {
...
date : "value
string
" ;
...
}
value
Any alphanumeric sequence.
Example
date : "1st Jan 2003" ;
dist_conversion_factor Simple Attribute
The dist_conversion_factor attribute specifies the distance resolution in the physical
library database. For example, when you specify a value of 1000, all the distance values
are stored in the database as 1/1000 of the distance_unit value.
Syntax
phys_library(library_name
id
) {
...
dist_conversion_factor : value
int
;
...
}
value
Valid values are any multiple of 10.
Example
dist_conversion_factor : 1000 ;
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distance_unit Simple Attribute
The distance attribute specifies unitLengthName attributeattributesunitLengthNamethe linear distance unit.
Syntax
phys_library(library_name
id
) {
...
distance_unit : value
enum
;
...
}
value
Valid values are 1mm and 1um.
Example
distance_unit : 1mm ;
frequency_conversion_factor Simple Attribute
The frequency_conversion_factor attribute specifies the frequency resolution in
the physical library database. For example, when you specify a value of 1000, all the
frequency values are stored in the database as 1/1000 of the frequency_unit value.
Syntax
phys_library(library_name
id
) {
...
frequency_conversion_factor : value
int
...
}
value
Valid values are any multiple of 10.
Example
frequency_conversion_factor : 1 ;
frequency_unit Simple Attribute
The frequency_unit attribute specifies the frequency unit.
Syntax
phys_library(library_name
id
) {
...
frequency_unit : value
enum
;
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...
}
value
The valid value is 1mhz.
Example
frequency_unit : 1mhz ;
has_wire_extension Simple Attribute
The has_wire_extension attribute specifies whether wires are extended by a half width
at pins.
Syntax
phys_library(library_name
id
) {
...
has_wire_extension : value
Boolean
;
...
}
value
Valid values are TRUE (default) and FALSE.
Example
has_wire_extension : TRUE ;
inductance_conversion_factor Simple Attribute
The inductance_conversion_factor attribute specifies the inductance resolution in
the physical library database. For example, when you specify a value of 1000, all the
inductance values are stored in the database as 1/1000 of the inductance_unit value.
Syntax
phys_library(library_name
id
) {
...
inductance_conversion_factor : value
int
;
...
}
value
Valid values are any multiple of 10.
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Example
inductance_conversion_factor : 1000 ;
inductance_unit Simple Attribute
The inductance_unit attribute specifies the unit for inductance.
Syntax
phys_library(library_nameid) {
...
inductance_unit : value
enum
;
...
}
value
Valid values are 1fh, 1ph, 1nh, 1uh, 1mh, and 1h.
Example
inductance_unit : 1ph ;
is_incremental_library Simple Attribute
The is_incremental_library attribute specifies whether this library is only a partial
library which is meant to be used as an extension of a primary library.
Syntax
phys_library(library_name
id
) {
...
is_incremental_library : value
Boolean
;
...
}
value
Valid values are TRUE (default) and FALSE.
Example
is_incremental_library : TRUE ;
manufacturing_grid Simple Attribute
The manufacturing_grid attribute defines the manufacture grid resolution in the physical
library database. This is the smallest geometry size in this library for this process and uses
the unit defined in the distance_unit attribute.
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Syntax
phys_library(library_name
id
) {
...
manufacturing_grid : value
float
;
...
}
value
Valid values are any positive floating-point number.
Example
manufacturing_grid : 100 ;
power_conversion_factor Simple Attribute
The power_conversion_factor attribute specifies the factor to use for power conversion.
Syntax
phys_library(library_name
id
) {
...
power_conversion_factor : value
int
;
...
}
value
Valid values are any positive integer.
Example
time_conversion_factor : 100 ;
power_unit Simple Attribute
The power_unit attribute specifies the unit for power.
Syntax
phys_library(library_name
id
) {
...
power_unit : value
enum
;
...
}
value
Valid values are 1uw, 10uw, 100uw, 1mw. 10mw, 100mw, and 1w.
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Example
power_unit : 100 ;
resistance_conversion_factor Simple Attribute
The resistance_conversion_factor attribute specifies the resistance resolution in
the physical library database. For example, when you specify a value of 1000, all the
resistance values are stored in the database as 1/1000 of the resistance_unit value.
Syntax
phys_library(library_name
id
) {
...
resistance_conversion_factor : value
int
;
...
}
value
Valid values are any multiple of 10.
Example
resistance_conversion_factor : 1000 ;
resistance_unit Simple Attribute
The resistance_unit attribute specifies the unit for resistance.
Syntax
phys_library(library_nameid) {
...
resistance_unit : value
enum
;
...
}
value
Valid values are 1mohm, 1ohm, 10ohm, 100ohm, 1kohm, and 1Mohm.
Example
resistance_unit : 1ohm ;
revision Simple Attribute
This optional attribute lets you specify the library revision number.
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Attributes and Groups
Syntax
phys_library(library_name
id
) {
...
revision : "value
string
";
...
}
value
Any alphanumeric sequence.
Example
revision : "Revision 2.0.5" ;
SiO2_dielectric_constant Simple Attribute
Use the SiO2_dielectric_constant attribute to specify the relative permittivity of SiO2
that is to be used to calculate sidewall capacitance.
You determine the dielectric unit by dividing the unit for measuring capacitance by the unit
for measuring distance. For example,
Syntax
phys_library(library_name
id
) {
...
Si02_dielectric_constant : "value
float
";
...
}
value
A floating-point number representing the constant.
Example
Si02_dielectric_constant : 3.9 ;
time_conversion_factor Simple Attribute
The time_conversion_factor attribute specifies the factor to use for time conversions.
Syntax
phys_library(library_name
id
) {
...
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time_conversion_factor : value
int
;
...
}
value
Valid values are any positive integer.
Example
time_conversion_factor : 100 ;
time_unit Simple Attribute
The time_unit attribute specifies the unit for time.
Syntax
phys_library(library_name
id
) {
...
time_unit : value
enum
;
...
}
value
Valid values are 1ns, 100ps, 10ps, and 1ps.
Example
time_unit : 100 ;
voltage_conversion_factor Simple Attribute
The voltage_conversion_factor attribute specifies specifies the factor to use for
voltage conversions.
Syntax
phys_library(library_name
id
) {
...
voltage_conversion_factor : value
int
;
...
}
value
Valid values are any positive integer.
Example
voltage_conversion_factor : 100 ;
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voltage_unit Simple Attribute
The voltage_unit attribute specifies the unit for voltage.
Syntax
phys_library(library_name
id
) {
...
voltage_unit : value
enum
;
...
}
value
Valid values are 1mv, 10mv, 100mv, and 1v.
Example
voltage_unit : 100 ;
antenna_lut_template Group
The antenna_lut_template group defines the table template used to specify the
antenna_ratio table. The antenna_ratio table is a one-dimensional template that
accepts only antenna_diffusion_area limit as a valid value.
Syntax
phys_library(library_name
id
) {
...
antenna_lut_template (template_name
id
) {
...description...
}
...
}
template_name
The name of this lookup table template.
Example
antenna_lut_template (antenna_template_1) {
...
}
Simple Attribute
variable_1
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Complex Attribute
index_1
variable_1 Simple Attribute
The variable_1 attribute specifies the antenna diffusion area.
Syntax
phys_library(library_name
id
) {
...
antenna_lut_template (template_name
id
) {
variable_1 : variable_name
id
;
...
}
...
}
variable_name
The only valid value for variable_1 is antenna_diffusion_area.
Example
antenna_lut_template (antenna_template_1) {
variable_1 : antenna_diffusion_area ;
}
index_1 Complex Attribute
The index_1 attribute specifies the default indexes.
Syntax
phys_library(library_name
id
) {
...
antenna_lut_template(template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
antenna_lut_template (antenna_template_1) {
index_1 (0.0, 0.159, 0.16) ;
}
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resistance_lut_template Group
The resistance_lut_template group defines the template referenced by the
resistance_table group.
Syntax
phys_library(library_name
id
) {
...
resistance_lut_template (template_name
id
) {
...description...
}
...
}
template_name
The name of this lookup table template.
Example
resistance_lut_template (resistance_template_1) {
...
}
Simple Attributes
variable_1
variable_2
Complex Attributes
index_1
index_2
variable_1 and variable_2 Simple Attributes
Use these attributes to specify whether the variable represents the routing width or the
routing spacing.
Syntax
phys_library(library_name
id
) {
...
resistance_lut_template (template_name
id
) {
variable_1 : routing_type
id
;
variable_2 : routing_type
id
;
...
}
...
}
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routing_type
Valid values are routing_width and routing_spacing. The values for
variable_1 and variable_2 must be different.
index_1 and index_2 Complex Attributes
Use these attributes to specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
resistance_lut_template (template_name
id
) {
...
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
resistance_lut_template (resistance_template_1) {
variable_1 : routing_width ;
variable_2 : routing_spacing ;
index_1 (0.2, 0.4, 0.6, 0.8);
index_2 (0.1, 0.3, 0.5, 0.7);
}
shrinkage_lut_template Group
The shrinkage_lut_template group defines the template referenced by the
shrinkage_table group.
Syntax
phys_library(library_name
id
) {
...
shrinkage_lut_template (template_name
id
) {
...description...
}
...
}
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template_name
The name of this lookup table template.
Example
shrinkage_lut_template (shrinkage_template_1) {
...
}
Simple Attributes
variable_1
variable_2
Complex Attributes
index_1
index_2
variable_1 and variable_2 Simple Attributes
Use these attributes to specify whether the variable represents the routing width or the
routing spacing.
Syntax
phys_library(library_name
id
) {
...
shrinkage_lut_template (template_name
id
) {
variable_1 : routing_type
id
;
variable_2 : routing_type
id
;
...
}
...
}
routing_type
Valid values are routing_width and routing_spacing. The values for
variable_1 and variable_2 must be different.
index_1 and index_2 Complex Attributes
Use these attributes to specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
shrinkage_lut_template (template_name
id
) {
...
index_1 (value
float
, value
float
, value
float
, ...);
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index_2 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
shrinkage_lut_template (resistance_template_1) {
variable_1 : routing_width ;
variable_2 : routing_spacing ;
index_1 (0.3, 0.7, 0.8, 1.2);
index_2 (0.2, 0.4, 0.9, 1.1);
}
spacing_lut_template Group
The spacing_lut_template group defines the template referenced by the
spacing_table group.
Syntax
phys_library(library_name
id
) {
...
spacing_lut_template (template_name
id
) {
...description...
}
...
}
template_name
The name of this lookup table template.
Example
spacing_lut_template (spacing_template_1) {
...
}
Simple Attributes
variable_1
variable_2
variable_3
Complex Attributes
index_1
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index_2
index_3
variable_1, variable_2, and variable_3 Simple Attributes
Use these attributes to specify whether the variable represents the routing width or the
routing spacing.
Syntax
phys_library(library_name
id
) {
...
spacing_lut_template (template_name
id
) {
variable_1 : routing_type
id
;
variable_2 : routing_type
id
;
variable_3 : routing_type
id
;
...
}
...
}
routing_type
The valid value for variable_1 is routing_width. The valid values for
variable_2 are routing_width and routing_length. The valid value for
variable_3 is routing_length.
index_1, index_2, and index_3 Complex Attributes
Use these attributes to specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
spacing_lut_template (template_name
id
) {
...
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
index_3 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
spacing_lut_template (resistance_template_1) {
variable_1 : routing_width ;
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variable_2 : routing_width ;
variable_3 : routing_length ;
index_1 (0.3, 0.6, 0.9, 1.2);
index_2 (0.3, 0.6, 0.9, 1.2);
index_2 (1.2, 2.4, 3.8, 5.0);
}
wire_lut_template Group
The wire_lut_template group defines the template referenced by the
wire_extension_range_table group.
Syntax
phys_library(library_name
id
) {
...
wire_lut_template (template_name
id
) {
...description...
}
...
}
template_name
The name of this lookup table template.
Example
wire_lut_template (wire_template_1) {
...
}
Simple Attributes
variable_1
variable_2
variable_3
Complex Attributes
index_1
index_2
index_3
variable_1, variable_2, and variable_3 Simple Attributes
Use these attributes to specify the routing widths and lengths.
Syntax
phys_library(library_name
id
) {
...
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wire_lut_template (template_name
id
) {
variable_1 : routing_type
id
;
variable_2 : routing_type
id
;
variable_3 : routing_type
id
;
...
}
...
}
routing_type
The valid values for variable_1 and variable_2 are routing_width,
routing_length, top_routing_width, bottom_routing_width,
extension_width, and extension_length. The valid values for variable_3
are routing_width, routing_length, extension_width, and extension_length.
index_1, index_2, and index_3 Complex Attributes
Use these attributes to specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
wire_lut_template (template_name
id
) {
...
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
index_3 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
wire_lut_template (resistance_template_1) {
variable_1 : routing_width ;
variable_2 : routing_width ;
variable_3 : routing_length ;
index_1 (0.3, 0.6, 0.9, 1.2);
index_2 (0.3, 0.6, 0.9, 1.2);
index_2 (1.2, 2.4, 3.8, 5.0);
}
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Specifying Attributes in the resource Group
You use the resource group to specify the process architecture (standard cell or array)
and to specify the layer information (such as routing or contact layer). The resource group
is defined inside the phys_library group and must be defined before you model any cell.
The information in this chapter includes a description and syntax example for the attributes
that you can define within the resource group.
Syntax for Attributes in the resource Group
The following sections describe the syntax for the attributes you need to define in the
resource group. The syntax for the groups you can define within the resource group are
described in Chapter 3.
resource Group
The resource group specifies the process architecture class. You must define a resource
group before you define any macro group. Also, you can have only one resource group in
a physical library.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
...
}
}
architecture
Valid values are std_cell (standard cell technology) and array (gate array
technology).
Example
resource(std_cell) {
...
}
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Complex Attributes
contact_layer
device_layer
overlap_layer
substrate_layer
Note:
You must specify the layer definition from the substrate out; that is, from the
layer closest to the substrate out to the layer farthest from the substrate. You
use the following attributes and groups to specify the layer definition:
Attributes: contact_layer, device_layer, and overlap_layer
Groups: poly_layer, and routing_layer.
Groups
array
cont_layer
implant_layer
ndiff_layer
pdiff_layer
poly_layer
routing_layer
routing_wire_model
site
tile
via
contact_layer Complex Attribute
The contact_layer attribute defines the contact cut layer that enables current to flow
between the device and the first routing layer, or between any two routing layers.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
...
contact_layer(layer_name
id
) ;
...
}
}
layer_name
The name of the contact layer.
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Example
contact_layer(cut01) ;
device_layer Complex Attribute
The device_layer attribute specifies the layers that are fixed in the base array.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
...
device_layer(layer_name
id
) ;
...
}
}
layer_name
The name of the device layer.
Example
device_layer(poly) ;
overlap_layer Complex Attribute
The overlap_layer attribute specifies a layer for describing a rectilinear footprint of a cell.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
...
overlap_layer(layer_name
id
) ;
...
}
}
layer_name
The name of the overlap layer.
Example
overlap_layer(ovlp1) ;
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substrate_layer Complex Attribute
The substrate_layer attribute specifies a substrate layer.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
...
substrate_layer(layer_name
id
) ;
...
}
}
layer_name
The name of the substrate layer.
Example
substrate_layer(ovlp1) ;
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Specifying Groups in the resource Group
You use the resource group to specify the process architecture (standard cell or array)
and to specify the layer information (such as routing or contact layer). The resource group
is defined inside the phys_library group and must be defined before you model any cell.
This chapter describes the following groups:
•
array Group
•
cont_layer Group
• implant_layer Group
•
ndiff_layer Group
•
pdiff_layer Group
• poly_layer Group
•
routing_layer Group
•
routing_wire_model Group
•
site Group
•
tile Group
•
via Group
•
via_array_rule Group
Syntax for Groups in the resource Group
The following sections describe the groups you define in the resource group.
array Group
Use this group to specify the base array for a gate array architecture.
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Syntax for Groups in the resource Group
Syntax
phys_library(library_nameid) {
resource(architecture
enum
) {
array(array_name
id
) {
...
}
}
}
array_name
Specifies a name for the base array.
Note:
Standard cell technologies do not contain array definitions.
Example
array(ar1) {
...
}
Groups
floorplan
routing_grid
tracks
floorplan Group
Use this group to specify the arrangement of sites in your design.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
...
}
}
}
}
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Syntax for Groups in the resource Group
floorplan_name
Specifies the name of a floorplan. If you do not specify a name, this floorplan
becomes the default floorplan.
Example
floorplan(myPlan) {
...
}
Group
site_array
site_array Group
Use this group to specify an array of placement site locations.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
...
}
}
}
}
}
site_name
The name of a predefined site to be used for this array.
Example
site_array(core) {
...
}
Simple Attribute
orientation
Complex Attribute
iterate
origin
placement_rule
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orientation Simple Attribute
The orientation attribute specifies the site orientation when placed on the floorplan.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
orientation : value
enum
;
...
}
}
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 1.
Figure 1 Orientation Examples
Example
orientation : E ;
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iterate Complex Attribute
The iterate attribute specifies how many times to iterate the site from the specified
origin.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
) ;
...
}
}
}
}
}
num_x, num_y
Floating-point numbers that represent the x and y iteration values.
space_x, space_y
Floating-point numbers that represent the spacing values.
Example
iterate(20, 40, 55.200, 16.100) ;
origin Complex Attribute
The origin attribute specifies the point in the floorplan where you can place the first
instance of your array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
origin(num_x
float
, num_y
float
) ;
...
}
}
}
}
}
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num_x, num_y
Floating-point numbers that specify the x- and y-coordinates for the starting
point of your array.
Example
origin(-1.00, -1.00) ;
placement_rule Complex Attribute
The placement_rule attribute specifies whether you can place an instance on the
specified site array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
placement_rule : value
enum
;
...
}
}
}
}
}
value
Valid values are regular, can_place, and cannot_occupy.
where
Value Description
regular Base array of sites occupying the floorplan.
can_place Sites are available for placement.
cannot_occupy Sites are not available for placement.
Example
placement_rule : can_place ;
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routing_grid Group
Use this group to specify the global cell grid overlaying the array, as shown in Figure 2. If
you do not specify a routing grid, the default grid is used.
Figure 2 A Routing Grid
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
routing_grid() {
routing_direction : value
enum
;
grid_pattern(start
float
, grids
int
,
space
float
) ;
}
}
}
Example
routing_grid() {
...
}
Simple Attribute
routing_direction
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Complex Attribute
grid_pattern
routing_direction Simple Attribute
The routing_direction attribute specifies the preferred grid routing direction.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
routing_grid() {
routing_direction : value
enum
;
...
}
}
}
}
value
Valid values are horizontal and vertical.
Example
routing_direction : horizontal ;
grid_pattern Complex Attribute
The grid_pattern attribute specifies the global cell grid pattern.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
routing_grid() {
grid_pattern(start
float
, grids
int
, space
float
) ;
...
}
}
}
}
start
A floating-point number that represents the grid starting point.
grids
A number that represents the number of grids in the specified routing direction.
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space
A floating-point number that represents the spacing between the respective
grids.
Example
grid pattern(1.0, 100, 2.0)
tracks Group
Use this group to specify the routing track grid for the gate array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
tracks() {
...
}
}
}
}
Note:
You must define at least one track group for horizontal routing and one group
for vertical routing.
Simple Attributes
layers
routing_direction
Complex Attribute
track_pattern
layers Simple Attribute
The layers attribute specifies a list of layers available for the tracks.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
tracks() {
layers: "layer1_name
id
, layer2_name
id
,
..., layern_name
id
" ;
...
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}
}
}
}
layer1_name, layer2_name, ..., layern_name
A list of layer names.
Example
layers: "m1, m3" ;
routing_direction Simple Attribute
The routing_direction attribute specifies the track direction and the possible routing
direction.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
tracks() {
...
routing_direction:value
enum
;
...
}
}
}
}
value
Valid values are horizontal and vertical.
Example
routing_direction: horizontal ;
track_pattern Complex Attribute
The track_pattern attribute specifies the track pattern.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
array(array_name
id
) {
tracks() {
...
track_pattern(start
float
,tracks
int
, spacing
float
) ;
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}
}
}
}
start, tracks, spacing
Specifies the starting-point coordinate, the number of tracks, and the space
between the tracks, respectively.
Example
track_pattern (1.40, 50, 10.5) ;
cont_layer Group
Use this group to specify values for the contact layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the contact layer.
Example
cont_layer() {
...
}
Simple Attributes
corner_min_spacing
max_stack_level
spacing
Groups
enclosed_via_rules
max_current_ac_absavg
max_current_ac_avg
max_current_ac_peak
max_current_ac_rms
max_current_dc_avg
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corner_min_spacing Simple Attribute
The corner_min_spacing attribute specifies the minimum spacing allowed between two
vias when their corners point to each other; otherwise specifies the minimum edge-to-edge
spacing.
Note:
The corner_min_spacing complex attribute in the
topological_design_rules group specifies the minimum distance between
two contact layers.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
cont_layer () {
...
corner_min_spacing : value
float
;
...
}
}
}
}
value
A positive floating-point number representing the spacing value.
Example
corner_min_spacing : 0.0 ;
max_stack_level Simple Attribute
The max_stack attribute specifies a value for the maximum number of stacked vias.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer() {
...
max_stack_level : value
int
;
...
}
}
}
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value
An integer representing the stack level.
Example
max_stack_level : 2 ;
spacing Simple Attribute
Defines the minimum separation distance between the edges of objects on the layer when
the objects are on different nets.
Syntax
phys_library(library_name
id
) {
...
resource(architecture
enum
) {
cont_layer () {
...
spacing : value
float
;
...
}
}
}
value
A positive floating-point number representing the minimum spacing value.
Example
spacing : 0.0 ;
enclosed_cut_rule Group
Use this group to specify the rules for cuts in the middle of the cut array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
enclosed_cut_rule() {
...
}
}
}
}
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Simple Attributes
max_cuts
max_neighbor_cut_spacing
min_cuts
min_enclosed_cut_spacing
min_neighbor_cut_spacing
max_cuts Simple Attribute
The max_cuts attribute specifies the maximum number of neighboring cuts allowed within
a specified space (range).
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer() {
enclosed_cut_rule(layer_name
id
) {
max_cuts : value
float
;
...
}
}
}
}
value
A floating-point number representing the number of cuts.
Example
max_cuts : 0.0 ;
max_neighbor_cut_spacing Simple Attribute
The max_neighbor_cut_spacing attribute specifies the spacing (range) around the cut on
the perimeter of the array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
enclosed_cut_rule(layer_name
id
) {
max_neighbor_cut_spacing : value
float
;
...
}
}
}
}
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value
A floating-point number representing the spacing.
Example
max_neighbor_cut_spacing : 0.0 ;
min_cuts Simple Attribute
The min_cuts attribute specifies the minimum number of neighboring cuts allowed within
a specified space (range).
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
enclosed_cut_rule(layer_name
id
) {
min_cuts : value
float
;
...
}
}
}
}
value
A floating-point number representing the number of cuts.
Example
min_cuts : 0.0 ;
min_enclosed_cut_spacing Simple Attribute
The min_enclosed_cut_spacing attribute specifies the spacing (range) around the cut on
the perimeter of the array.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
enclosed_cut_rule(layer_name
id
) {
min_enclosed_cut_spacing : value
float
;
...
}
}
}
}
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value
A floating-point number representing the spacing.
Example
min_enclosed_via_spacing : 0.0 ;
min_neighbor_cut_spacing Simple Attribute
The min_neighbor_cut_spacing attribute specifies minimum spacing around the
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
enclosed_cut_rule(layer_name
id
) {
min_neighbor_via_spacing : value
float
;
...
}
}
}
}
value
A floating-point number representing the spacing around the cut on the
perimeter of the array..
Example
min_neighbor_cut_spacing : 0.0 ;
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
max_current_ac_absavg(template_name
id
) {
...
}
}
}
}
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template_name
The name of the contact layer.
Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
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max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
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template_name
The name of the contact layer.
Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
cont_layer () {
...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
Complex Attributes
index_1
index_2
values
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implant_layer Group
Use this group to specify the legal placement rules when mixing high drive and low drive
cells in the detail placement.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
implant_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the implant layer.
Simple Attributes
min_width
spacing
Complex Attribute
spacing_from_layer
min_width Simple Attribute
The min_width attribute specifies minWidth, layout attributelayout attributesminWidththe minimum width of any dimension of an object on the
layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
implant_layer(layer_name
id
) {
min_width : value
float
;
...
}
}
}
value
A floating-point number representing the width.
Example
min_width : 0.0 ;
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spacing Simple Attribute
The spacing attribute specifies the separation distance between the edges of objects on
the layer when the objects are on different nets.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
implant_layer(layer_name
id
) {
spacing : value
float
;
...
}
}
}
value
A floating-point number representing the spacing.
Example
spacing : 0.0 ;
spacing_from_layer Complex Attribute
The spacing_from_layer attribute specifies the minimum allowable spacing between two
geometries on the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
implant_layer(layer_name
id
) {
spacing_from_layer (value
float
, name
id
);
...
}
}
}
value
A floating-point number representing the spacing.
name
A layer name.
Example
spacing_from_layer () ;
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ndiff_layer Group
Use the ndiff_layer group to specify the maximum current values for the n-diffusion
layer.
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
ndiff_layer () {
...
max_current_ac_absavg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
ndiff_layer () {
...
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max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
ndiff_layer () {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
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Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
ndiff_layer () {
...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
ndiff_layer () {
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...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
Complex Attributes
index_1
index_2
values
pdiff_layer Group
Use the pdiff_layer group to specify the maximum current values for the p-diffusion
layer.
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff_layer () {
...
max_current_ac_absavg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
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Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff_layer () {
...
max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff_layer () {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff_layer () {
...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
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Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff_layer () {
...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
Complex Attributes
index_1
index_2
values
poly_layer Group
Use this group to specify the poly layer name and properties.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the poly layer.
Example
poly_layer() {
...
}
Simple Attributes
avg_lateral_oxide_permittivity
avg_lateral_oxide_thickness
height
oxide_permittivity
oxide_thickness
res_per_sq
shrinkage
thickness
Complex Attributes
conformal_lateral_oxide
lateral_oxide
Groups
max_current_ac_absavg
max_current_ac_avg
max_current_ac_peak
max_current_ac_rms
max_current_dc_avg
avg_lateral_oxide_permittivity Simple Attribute
This attribute specifies a value representing the average lateral oxide permittivity.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
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poly_layer(layer_name
id
) {
avg_lateral_oxide_permittivity : value
float
;
...
}
}
}
permittivity
A floating-point number that represents the lateral oxide permittivity.
Example
avg_lateral_oxide_permittivity (0.0 ) ;
avg_lateral_oxide_thickness Simple Attribute
This attribute specifies a value representing the average lateral oxide thickness.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
avg_lateral_oxide_thickness : value
float
;
...
}
}
}
thickness
A floating-point number that represents the lateral oxide thickness.
Example
avg_lateral_oxide_thickness (0.0) ;
height Simple Attribute
The height attribute specifies the distance from the top of the substrate to the bottom of
the routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
height : type_name
float
;
...
}
}
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}
type_name
A floating-point number representing the distance.
Example
height : 1.0 ;
oxide_permittivity Simple Attribute
The oxide_permittivity attribute specifies the oxide permittivity for the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
oxide_permittivity : value
float
;
...
}
}
}
value
A floating-point number representing the permittivity.
Example
oxide_permittivity : 3.9 ;
oxide_thickness Simple Attribute
The oxide_thickness attribute specifies the oxide thickness for the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
oxide_thickness : value
float
;
...
}
}
}
float
A floating-point number representing the thickness.
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Example
oxide_thickness : 2.0 ;
res_per_sq Simple Attribute
The res_per_sq attribute specifies the resistance unit area of a poly layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
res_per_sq : value
float
;
...
}
}
}
value
A floating-point number representing the resistance value.
Example
res_per_sq : 1.200e-01 ;
shrinkage Simple Attribute
The shrinkage attribute specifies the total distance by which the wire width on the layer
shrinks or expands. The shrinkage parameter is a sum of the shrinkage for each side of
the wire. The post-shrinkage wire width represents the final processed silicon width as
calculated from the drawn silicon width in the design database.
Note:
Do not specify a value for the shrinkage attribute or shrinkage_table group if
you specify a value for the process_scale_factor attribute.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
shrinkage : value
float
;
...
}
}
}
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value
A floating-point number representing the distance. A positive number represents
shrinkage; a negative number represents expansion.
Example
shrinkage : 0.00046 ;
thickness Simple Attribute
The thickness attribute specifies the thickness of the routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
thickness : value
float
;
...
}
}
}
value
A floating-point number representing the thickness.
Example
thickness : 0.02 ;
conformal_lateral_oxide Complex Attribute
The conformal_lateral_oxide attribute specifies values for the thickness and
permittivity of a layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
conformal_lateral_oxide(value_1
float
,value_2
float
,\
value_3
float
, value_4
float
) ;
...
}
}
}
value_1
A floating-point number that represents the oxide thickness.
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value_2
A floating-point number that represents the topwall thickness.
value_3
A floating-point number that represents the sidewall thickness.
value_4
A floating-point number that represents the oxide permittivity.
Example
conformal_lateral_oxide (0.2, 0.3, 0.21, 3.5) ;
lateral_oxide Complex Attribute
The lateral_oxide attribute specifies values for the thickness and permittivity of a layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
poly_layer(layer_name
id
) {
lateral_oxide(thickness
float
, permittivity
float
) ;
...
}
}
}
thickness
A floating-point number that represents the oxide thickness.
permittivity
A floating-point number that represents the oxide permittivity.
Example
lateral_oxide (0.024, 3.6) ;
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff () {
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...
max_current_ac_absavg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff () {
...
max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
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Complex Attributes
index_1
index_2
index_3
values
max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff () {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff () {
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...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
pdiff () {
...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
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Complex Attributes
index_1
index_2
values
routing_layer Group
Use this group to specify the routing layer name and properties.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the routing layer.
Example
routing_layer(m1) {
...
}
Simple Attributes
avg_lateral_oxide_permittivity
avg_lateral_oxide_thickness
baseline_temperature
cap_multiplier
cap_per_sq
coupling_cap
default_routing_width
edgecapacitance
field_oxide_permittivity
field_oxide_thickness
fill_active_spacing
fringe_cap
height
inductance_per_dist
max_current_density
max_length
max_observed_spacing_ratio_for_lpe
max_width
min_area
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min_enclosed_area
min_enclosed_width
min_fat_wire_width
min_fat_via_width
min_length
min_width
min_wire_split_width
offset
oxide_permittivity
oxide_thickness
pitch
process_scale_factor
res_temperature_coefficient
routing_direction
same_net_min_spacing
shrinkage
spacing
thickness
u_shaped_wire_spacing
wire_extension
wire_extension_range_check_connect_only
wire_extension_range_check_corner_only
Complex Attribute
conformal_lateral_oxide
lateral_oxide
min_extension_width
min_shape_edge
plate_cap
ranged_spacing
spacing_check_style
stub_spacing
Groups
end_of_line_spacing_rule
extension_via_rule
max_current_ac_absavg
max_current_ac_avg
max_current_ac_peak
max_current_ac_rms
max_current_dc_avg
min_edge_rule
min_enclosed_area_table
notch_rule
resistance_table
shrinkage_table
spacing_table
wire_extension_range_table
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avg_lateral_oxide_permittivity Simple Attribute
This attribute specifies a value representing the average lateral oxide permittivity.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
avg_lateral_oxide_permittivity : value
float
;
...
}
}
}
permittivity
A floating-point number that represents the lateral oxide permittivity.
Example
avg_lateral_oxide_permittivity (0.0 ) ;
avg_lateral_oxide_thickness Simple Attribute
This attribute specifies a value representing the average lateral oxide thickness.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
avg_lateral_oxide_thickness : value
float
;
...
}
}
}
thickness
A floating-point number that represents the lateral oxide thickness.
Example
avg_lateral_oxide_thickness (0.0) ;
baseline_temperature Simple Attribute
This attribute specifies a baseline operating condition temperature.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
baseline_temperature : value
float
;
...
}
}
}
value
A floating-point number representing the temperature.
Example
baseline_temperature : 60.0 ;
cap_multiplier Simple Attribute
Use the cap_multiplier attribute to specify a scaling factor for interconnect capacitance
to account for changes in capacitance due to nearby wires.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
cap_multiplier : value
float
;
...
}
}
}
value
A floating-point number representing the scaling factor.
Example
cap_multiplier : 2.0
cap_per_sq Simple Attribute
The cap_per_sq attribute specifies the substrate capacitance per unit area of a routing
layer.
Syntax
phys_library(library_name
id
) {
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resource(architecture
enum
) {
routing_layer(layer_name
id
) {
cap_per_sq : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance for a square unit of wire,
in picofarads per square distance unit.
Example
cap_per_sq : 5.909e-04 ;
coupling_cap Simple Attribute
The coupling_cap attribute specifies the coupling capacitance per unit length between
parallel wires on the same layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
coupling_cap : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance value.
Example
coupling_cap: 0.000019 ;
default_routing_width Simple Attribute
The default_routing_width attribute specifies the minimal routing width (default) for
wires on the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
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default_routing_width : value
float
;
...
}
}
}
value
A positive floating-point number representing the default routing width.
Example
default_routing : 4.400e-01 ;
edgecapacitance Simple Attribute
The edgecapacitance attribute specifies the total peripheral capacitance per unit length
of a wire on the routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
edgecapacitance : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance per unit length value.
Example
edgecapacitance : 0.00065 ;
field_oxide_permittivity Simple Attribute
The field_oxide_permittivity attribute specifies the relative permittivity of the field
oxide.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
field_oxide_permittivity : value
float
;
...
}
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}
}
value
A positive floating-point number representing the relative permittivity.
Example
field_oxide_permittivity : 3.9 ;
field_oxide_thickness Simple Attribute
The field_oxide_thickness attribute specifies the field oxide thickness.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
field_oxide_thickness : value
float
;
...
}
}
}
value
A positive floating-point number in distance units.
Example
field_oxide_thickness : 0.5 ;
fill_active_spacing Simple Attribute
The fill_active_spacing attribute specifies the spacing between fill metal and active
geometry.
Syntax
phys_library(value
float
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
fill_active_spacing : value
float
;
...
}
}
}
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value
A floating-point number that represents the spacing.
Example
fill_active_spacing : 0.0 ;
fringe_cap Simple Attribute
The fringe_cap attribute specifies the fringe (sidewall) capacitance per unit length of a
routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
fringe_cap : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance value.
Example
fringe_cap : 0.00023 ;
height Simple Attribute
The height attribute specifies the distance from the top of the substrate to the bottom of
the routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
height : value
float
;
...
}
}
}
value
A floating-point number representing the distance.
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Example
height : 1.0 ;
inductance_per_dist Simple Attribute
The inductance_per_dist attribute specifies the inductance per unit length of a routing
layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
inductance_per_dist : value
float
;
...
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance_per_dist : 0.0029 ;
max_current_density Simple Attribute
The max_current_density attribute specifies the maximum current density for a contact.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
max_current_density : value
float
;
...
}
}
}
value
A floating-point number that represents, in amperes per centimeter, the
maximum current density the contact can carry.
Example
max_current_density : 0.0 ;
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max_length Simple Attribute
The max_length attribute specifies the maximum length of wire segments on the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
max_length : value
float
;
...
}
}
}
value
A floating-point number that represents wire segment length.
Example
max_length : 0.0 ;
max_observed_spacing_ratio_for_lpe Simple Attribute
This attribute specifies the maximum wire spacing for layer parasitic extraction (LPE) when
calculating intracapacitance.
Use the true spacing value for calculating intracapacitance when the spacing between all
wires reflects the following equation:
distances < spacing * max_observed_spacing_ratio_for_lpe
Use a calculated value as shown for calculating intracapacitance when the spacing
between all wires reflects the following equation.
distances > (spacing * max_observed_spacing_ratio_for_lpe)
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
max_observed_spacing_ratio_for_lpe : value
float
;
...
}
}
}
value
A floating-point number that represents the distance.
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Example
max_observed_spacing_ratio_for_lpe : 3.0 ;
max_width Simple Attribute
The max_width attribute specifies the maximum width of wire segments on the layer for
DRC.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
max_width : value
float
;
...
}
}
}
value
A floating-point number that represents wire segment width.
Example
max_width : 0.0 ;
min_area Simple Attribute
The min_area attribute specifies the minimum metal area for the given routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_area : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum metal area.
Example
min_area : 0.0 ;
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min_enclosed_area Simple Attribute
The min_enclosed_area attribute specifies the minimum metal area, enclosed by ring-
shaped wires or vias, for the given routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_enclosed_area : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum metal area.
Example
min_enclosed_area : 0.14 ;
min_enclosed_width Simple Attribute
The min_enclosed_width attribute specifies the minimum metal width for the given
routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_enclosed_width : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum metal width.
Example
min_enclosed_width : 0.14 ;
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min_fat_wire_width Simple Attribute
The min_fat_wire_width attribute specifies the minimal wire width that defines whether a
wire is a fat wire.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_fat_wire_width : value
float
;
...
}
}
}
value
A floating-point number that represents the minimal wire width.
Example
min_fat_wire_width : 0.0 ;
min_fat_via_width Simple Attribute
The min_fat_via_width attribute specifies a threshold value fatWireThreshold, fat wire attributefat wire attributesfatWireThresholdfor using the fat wire
spacing rule instead of the default spacing rule
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_fat_via_width : value
float
;
...
}
}
}
value
A floating-point number that represents the threshold value.
Example
min_fat_via_width : 0.0 ;
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min_length Simple Attribute
The min_length attribute specifies the minimum length of wire segments on the layer for
DRC.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_length : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum wire segment length.
Example
min_length : 0.202 ;
min_width Simple Attribute
The min_width attribute specifies the minimum width of wire segments on the layer for
DRC.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_width : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum wire segment width.
Example
min_width : 0.202 ;
min_wire_split_width Simple Attribute
This attribute specifies the minimum wire width for split wires.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_wire_split_width : value
float
;
...
}
}
}
value
A floating-point number that represents the minimum wire split width.
Example
min_wire_split_width : 0.202 ;
offset Simple Attribute
The offset attribute specifies the offset distance from the placement grid to the routing
grid. The default is one half the routing pitch value.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
offset : value
float
;
...
}
}
}
value
A floating-point number representing the distance.
Example
offset : 0.0025 ;
oxide_permittivity Simple Attribute
The oxide_permittivity attribute specifies the permittivity for the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
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routing_layer(layer_name
id
) {
oxide_permittivity : value
float
;
...
}
}
}
value
A floating-point number representing the permittivity.
Example
oxide_permittivity : 3.9 ;
oxide_thickness Simple Attribute
The oxide_thickness attribute specifies the oxide thickness for the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
oxide_thickness : value
float
;
...
}
}
}
value
A floating-point number representing the thickness.
Example
oxide_thickness : 1.33 ;
pitch Simple Attribute
The pitch attribute specifies the track distance (center point to center point) of the detail
routing grid for a standard-cell routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
pitch : value
float
;
...
}
}
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}
value
A floating-point number representing the specified distance.
Example
pitch : 8.400e-01 ;
process_scale_factor Simple Attribute
This attribute specifies the factor to use before RC calculation to scale the length, width,
and spacing.
Note:
Do not specify a value for the process_scale_factor attribute if you specify a
value for the shrinkage attribute or shrinkage_table group.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
process_scale_factor : value
float
;
...
}
}
}
value
A floating-point number representing the scaling factor.
Example
process_scale_factor : 0.95 ;
res_per_sq Simple Attribute
The res_per_sq attribute specifies the resistance unit area of a routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
res_per_sq : value
float
;
...
}
}
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}
value
A floating-point number representing the resistance value.
Example
res_per_sq : 1.200e-01 ;
res_temperature_coefficient Simple Attribute
Use the temperatureCoeff attribute to define the coefficient of the first-order correction
to the resistance per square when the operating temperature is not equal to the nominal
temperature at which the resistance per square variables are defined.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
value
A floating-point number representing the temperature coefficient.
Example
res_temperature_coefficient : 0.00 ;
routing_direction Simple Attribute
The routing_direction attribute specifies the preferred direction for routing wires.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
routing_direction : value
enum
;
...
}
}
}
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value
Valid values are horizontal and vertical.
Example
routing_direction : horizontal ;
same_net_min_spacing Simple Attribute
This attribute specifies a smaller spacing distance rule than the default rule for two shapes
belonging to the same net.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
same_net_min_spacing : value
float
;
...
}
}
}
value
A floating-point number representing the spacing distance.
Example
same_net_min_spacing : 0.04 ;
shrinkage Simple Attribute
The shrinkage attribute specifies the total distance by which the wire width on the layer
shrinks or expands. The shrinkage parameter is a sum of the shrinkage for each side of
the wire. The postshrinkage wire width represents the final processed silicon width as
calculated from the drawn silicon width in the design database.
Note:
Do not specify a value for the shrinkage attribute or shrinkage_table group if
you specify a value for the process_scale_factor attribute.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
shrinkage : value
float
;
...
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}
}
}
value
A floating-point number representing the distance. A positive number represents
shrinkage; a negative number represents expansion.
Example
shrinkage : 0.00046 ;
spacing Simple Attribute
The spacing attribute specifies the minimal (default) value for different net (edge to edge)
spacing for regular wiring on the layer. This spacing value applies to all routing widths
unless overridden by the ranged_spacing attribute in the same routing_layer group or
by the wire_rule group.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
spacing : value
float
;
...
}
}
}
value
A floating-point number representing the minimal different net spacing value.
Example
spacing : 3.200e-01 ;
thickness Simple Attribute
The thickness attribute specifies the nominal thickness of the routing layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
thickness : value
float
;
...
}
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}
}
value
A floating-point number representing the thickness.
Example
thickness : 0.02 ;
u_shaped_wire_spacing Simple Attribute
The u_shaped_wire_spacing attribute specifies that a u-shaped notch requires more
spacing between wires than the value of the spacing attribute allows.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
u_shaped_wire_spacing : value
float
;
...
}
}
}
value
A floating-point number that represents the spacing value.
Example
u_shaped_wire_spacing : 0.0 ;
wire_extension Simple Attribute
The wire_extension attribute specifies the distance for extending wires at vias.
Syntax
phys_library(library_nameid) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
wire_extension : value
float
;
...
}
}
}
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value
A floating-point number that represents the wire extension value. A zero value
specifies no wire extension. A nonzero value must be at least half the routing
width for the layer.
Example
wire_extension : 0.025 ;
wire_extension_range_check_connect_only Simple Attribute
This attribute specifies whether the projection length requires wide wire spacing.
Syntax
phys_library(library_nameid) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
wire_extension_range_check_connect_only : Boolean ;
...
}
}
}
value
Valid values are true and false.
Example
wire_extension_range_check_connect_only : true ;
wire_extension_range_check_corner Simple Attribute
This attribute specifies whether the projection length requires wide wire spacing.
Syntax
phys_library(library_nameid) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
wire_extension_range_check_corner : Boolean ;
...
}
}
}
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Boolean
Valid values are true and false.
Example
wire_extension_range_check_corner : true ;
conformal_lateral_oxide Complex Attribute
This attribute specifies values for the thickness and permittivity of a layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
conformal_lateral_oxide(value_1
float
, value_2
float
,\
value_3
float
, value_4
float
,) ;
...
}
}
}
value_1
A floating-point number that represents the oxide thickness.
value_2
A floating-point number that represents the topwall thickness.
value_3
A floating-point number that represents the sidewall thickness.
value_4
A floating-point number that represents the oxide permittivity.
Example
conformal_lateral_oxide (0.2, 0.3, 0.21, 3.6) ;
lateral_oxide Complex Attribute
The lateral_oxide attribute specifies values for the thickness and permittivity of a layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
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lateral_oxide(thickness
float
, permittivity
float
) ;
...
}
}
}
thickness
A floating-point number that represents the oxide thickness.
permittivity
A floating-point number that represents the oxide permittivity.
Example
lateral_oxide (0.)4, 3.9) ;
min_extension_width Complex Attribute
The min_extension_width attribute specifies the rules for a protrusion.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_extension_width (value_1
float
,
value_2
float
,value_3
float
);
...
}
}
}
value_1
A floating-point number that represents minimum wire width.
value_2
A floating-point number that represents the maximum extension length.
value_3
A floating-point number that represents the minimum extension width.
Example
min_extension_width () ;
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min_shape_edge Complex Attribute
For a polygon, this attribute specifies the maximum number of edges of minimum edge
length.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_shape_edge (length
float
, edges
int
);
...
}
}
}
length
A floating-point number that represents the minimum length of a polygon edge.
edges
An integer that represents the maximum number of polygon edges.
Example
min_shape_edge(0.02, 3) ;
plate_cap Complex Attribute
The plate_cap attribute specifies the interlayer capacitance per unit area when a wire on
the first routing layer overlaps a wire on the second routing layer.
Note:
The plate_cap statement must follow all the routing_layer statements and
precede the routing_wire_model statements.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
plate_cap(PCAP_la_lb
float
, PCAP_la_lb
float
,
PCAP_ln-1_ln
float
) ;
...
}
}
}
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PCAP_la_lb
Represents a floating-point number that specifies the plate capacitance per
unit area between two routing layers, layer a and layer b. The number of PCAP
values is determined by the number of previously defined routing layers. You
must specify every combination of routing layer pairs based on the order of the
routing layers. For example, if the layers are defined as substrate, layer1, layer2,
and layer3, then the PCAP values are defined in PCAP_l1_l2, PCAP_l1_l3, and
PCAP_l2_l3.
Example
The example shows a plate_cap statement for a library with four layers. The values are
indexed by the routing layer order.
plate_cap( 0.35, 0.06, 0.0, 0.25, 0.02, 0.15) ;
/* PCAP_1_2, PCAP_1_3, PCAP_1_4, PCAP_2_3, PCAP_2_4, PCAP_3_4 */
ranged_spacing Complex Attribute
The ranged_spacing attribute specifies the different net spacing (edge to edge) for
regular wiring on the layer. You can also use the ranged_spacing attribute to specify the
minimal spacing for a particular routing width range of the metal. You can use more than
one ranged_spacing attribute to specify spacings for different ranges.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
ranged_spacing(min_width
float
, max_width
float
,
spacing
float
);
...
}
}
}
min_width, max_width
Floating-point numbers that represent the minimum and maximum routing width
range.
spacing
A floating-point number that represents the spacing.
Example
ranged_spacing(2.5, 5.5, 1.3) ;
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spacing_check_style Complex Attribute
The spacing_check attribute specifies the minimum distance.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
spacing_check_style : check_style_name
enum
;
...
}
}
}
check_style_name
Valid values are manhattan and diagonal.
Example
spacing_check_style : diagonal ;
stub_spacing Complex Attribute
The stub_spacing attribute specifies the distances required between the edges of two
objects on a layer when the distance that the objects run parallel to each other is less than
or equal to a specified threshold.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
stub_spacing(layer_name
id
) {
stub_spacing (spacing
float
, max_length_threshold
float
,
min_wire_width
float
, max_wire_width
float
);
...
}
}
}
spacing
A floating-point number that is less than the minimum spacing value specified for
the layer.
max_length_threshold
A floating-point number that represents the maximum distance that two objects
on the layer can run parallel to each other.
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min_wire_width
A floating-point number that represents the minimum spacing to a neighbor wire
(optional).
max_wire_width
A floating-point number that represents the maximum spacing to a neighbor wire
(optional).
Example
stub_spacing(1.05, 0.08)
end_of_line_spacing_rule Group
Use the end_of_line_spacing_rule attribute to specify the spacing between a stub wire
and other wires.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
...
}
}
}
}
Simple Attributes
end_of_line_corner_keepout_width
end_of_line_edge_checking
end_of_line_metal_max_width
end_of_line_min_spacing
max_wire_width
Example
end_of_line_spacing_rule () {
...
}
end_of_line_corner_keepout_width Simple Attribute
This attribute specifies the corner keepout width.
Syntax
phys_library(library_name
id
) {
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resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
end_of_line_corner_keepout_width : value
Boolean
;
...
}
}
}
}
value
Valid values are 1 and 0.
Example
end_of_line_corner_keepout_width : 0.0 ;
end_of_line_edge_checking Simple Attribute
This attribute specifies the number of edges to check.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
end_of_line_edge_checking : value
enum
;
...
}
}
}
}
value
Valid values are one_edge, two_edges, and three_edges.
Example
end_of_line_edge_checking
end_of_line_metal_max_width Simple Attribute
The maximum distance between two objects on a layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
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end_of_line_metal_max_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the width.
Example
end_of_line_metal_max_width
end_of_line_min_spacing Simple Attribute
This attribute specifies the minimum distance required between the parallel edges of two
objects on the layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
end_of_line_min_spacing :value
float
;
...
}
}
}
}
value
A floating-point number representing the spacing.
Example
end_of_line_min_spacing : 0.0 ;
max_wire_width Simple Attribute
Use this attribute to specify the maximum wire width for the spacing rule.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
end_of_line_spacing_rule() {
max_wire_width :value
float
;
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...
}
}
}
}
value
A floating-point number representing the width.
Example
max_wire_width
extension_via_rule Group
Use this group to define specific via and minimum cut numbers for a given fat metal width
and extension range.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule() {
...
}
}
}
}
Simple Attribute
related_layer
Groups
min_cuts_table
reference_cut_table
Example
extension_via_rule ( ) {
...
}
related_layer
The related_layer attribute specifies the contact layer to which this rule applies.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule() {
related_layer : layer_name
id
;
...
}
}
}
}
layer_name
A string value representing the layer name.
Example
related_layer : ;
min_cuts_table Group
Use this group to specify the minimum number of vias.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule() {
min_cuts_table (template_name
id
) {
index_1("value
float
, value
float
, ...") ;
index_2("value
float
, value
float
, ...") ;
values ("value
float
, value
float
, ...") ;
}
}
}
}
}
wire_lut_template_name
The wire_lut_template name.
Complex Attributes
index_1
index_2
values
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index_1 and index_2 Complex Attributes
These attributes specify the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule() {
min_cuts_table(wire_lut_template_name
id
) {
index_1 ("value
float
, value
float
, ...") ;
index_2 ("value
float
, value
float
, ...") ;
values ("value
float
, value
float
, ...") ;
}
}
}
}
}
Example
extension_via_rule (template_name) {
index_1 ( "0.6. 0.8, 1.2" ) ;
index_2 ( "0.6, 0.8, 1.0" ) ;
values ( "0.07, 0.08, 0.09" ) ;
reference_cut_table Group
Use this group to specify a table of predefined via values.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule(via_array_lut_template_name
id
) {
reference_cut_table (wire_lut_template_name
id
) {
index_1("value
float
, value
float
, ...") ;
index_2("value
float
, value
float
, ...") ;
values ("value
float
, value
float
, ...") ;
}
}
}
}
}
via_array_lut_template_name
The via_array_lut_template name.
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Complex Attributes
index_1
index_2
values
index_1 and index_2 Complex Attributes
These attributes specify the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
extension_via_rule() {
index_1 ("value
float
, value
float
, value
float
, ...") ;
index_2 ("value
float
, value
float
, value
float
, ...") ;
values ("value
float
, value
float
, value
float
, ...") ;
}
}
}
}
Example
extension_via_rule (template_name) {
index_1 ( "0.6. 0.8, 1.2" ) ;
index_2 ( "0.6, 0.8, 1.0" ) ;
values ( "0.07, 0.08, 0.09" ) ;
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer () {
...
max_current_ac_absavg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
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Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer () {
...
max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer () {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer () {
...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
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Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer () {
...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
Complex Attributes
index_1
index_2
values
min_edge_rule Group
Use the min_edge_rule group to specify the minimum edge length rules.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_edge_rule() {
...
}
}
}
}
Example
min_edge_rule () {
...
}
Simple Attributes
concave_corner_required
max_number_of_min_edges
max_total_edge_length
min_edge_length
concave_corner_required Simple Attribute
This attribute specifies whether a concave corner triggers a violation of the minimum edge
length rules.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_edge_rule() {
concave_corner_required : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
concave_corner_required : TRUE ;
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max_number_of_min_edges Simple Attribute
This attribute specifies the maximum number of consecutive short (minimum) edges.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_edge_rule() {
max_number_of_min_edges : value
int
;
...
}
}
}
}
value
An integer value representing the number of edges.
Example
max_number_of_min_edges : 1 ;
max_total_edge_length Simple Attribute
This attribute specifies the maximum allowable total edge length.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_edge_rule() {
max_total_edge_length : value
float
;
...
}
}
}
}
value
A floating-point number representing the edge length.
Example
max_total_edge_length : 0.0 ;
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min_edge_length Simple Attribute
The min_edge_length attribute specifies the lengthminEdgeLength, physical attributephysical attributesminEdgeLength for defining short edges
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_edge_rule() {
min_edge_length : value
float
;
...
}
}
}
}
term
A floating-point number representing the edge length.
Example
min_edge_length : 0.0 ;
min_enclosed_area_table Group
Use this group to specify a range of values for an enclosed area.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_enclosed_area_table(wire_lut_template_name
id
) {
...
}
}
}
}
wire_lut_template_name
The wire_lut_template name.
Example
min_enclosed_area_table ( ) {
...
}
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Complex Attributes
index_1
values
index_1 Complex Attribute
The index_1 attribute specifies the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
min_enclosed_area_table(wire_lut_template_name
id
) {
index_1 ("value
float
, value
float
, value
float
, ...")
index_2 ("value
float
, value
float
, value
float
, ...")
values ("value
float
, value
float
, value
float
, ...") ;
}
}
}
}
Example
min_enclosed_area_table (template_name) {
index_1 ( "0.6. 0.8, 1.2" ) ;
values ( "0.07, 0.08, 0.09" ) ;
notch_rule Group
Use the notch_rule group to specify the notch rules.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
notch_rule() {
...
}
}
}
}
Example
notch_rule () {
...
}
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Simple Attributes
min_notch_edge_length
min_notch_width
min_notch_edge_length Simple Attribute
This attribute specifies the notch height.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
notch_rule() {
min_notch_edge_length : value
float
;
...
}
}
}
}
value
A floating-point number representing the notch height.
Example
min_notch_edge_length : 0.4 ;
min_notch_width Simple Attribute
This attribute specifies the notch width.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
notch_rule() {
min_notch_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the notch width.
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Example
min_notch_width : 0.26 ;
min_wire_width Simple Attribute
This attribute specifies the minimum wire width.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
notch_rule() {
min_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the wire width.
Example
min_wire_width : 0.26 ;
resistance_table Group
Use this group to specify an array of values for sheet resistance.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
resistance_table(template_name
id
) {
...
}
}
}
}
template_name
The name of a resistance_lut_template defined at the phys_library level.
Example
resistance_table ( ) {
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...
}
Complex Attributes
index_1
index_2
values
index_1 and index_2 Complex Attributes
These attributes specify the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
resistance_table(template_name
id
) {
index_1 ("value
float
, value
float
, value
float
, ...")
index_2 ("value
float
, value
float
, value
float
, ...")
values ("value
float
, value
float
, value
float
, ...") ;
}
}
}
}
Example
resistance_table (template_name) {
index_1 ( "0.6. 0.8, 1.2" ) ;
index_2 ( "0.6, 0.8, 1.0" ) ;
values ( "0.07, 0.08, 0.09" ) ;
shrinkage_table Group
Use this group to specify a lookup table template.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
shrinkage_table(template_name
id
) {
...
}
}
}
}
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template_name
The name of a shrinkage_lut_template defined at the phys_library level.
Example
shrinkage_table (shrinkage_lut) {
...
}
Complex Attributes
index_1
index_2
values
index_1 and index_2 Complex Attributes
These attributes specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
shrinkage_table (template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
values ("value
float
, value
float
, value
float
", "...", "...") ;
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the indexes for this shrinkage table and
the shrinkage table values.
Example
shrinkage_table (shrinkage_template_name) {
values ("0.02, 0.03, 0.04", "0.0,1 0.02, 0.03" );
}
spacing_table Group
Use this group to specify a lookup table template.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
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spacing_table(template_name
id
) {
...
}
}
}
}
template_name
The name of a spacing_lut_template defined at the phys_library level.
Example
spacing_table (spacing_template_1) {
...
}
Complex Attributes
index_1
index_2
index_3
values
index_1, index_2, index_3, and values Complex Attributes
These attributes specify the indexes and values for the spacing table.
Syntax
phys_library(library_name
id
) {
...
spacing_table (template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
index_3 (value
float
, value
float
, value
float
, ...);
values ("value
float
, value
float
, value
float
", "...",
"...") ;
}
...
}
value, value, value, ...
Floating-point numbers that represent the indexes and spacing table values.
Example
spacing_table (spacing_template_1) {
index_1 (0.0, 0.0, 0.0, 0.0);
index_2 (0.0, 0.0, 0.0, 0.0);
index_3 (0.0, 0.0, 0.0, 0.0);
values (0.0, 0.0, 0.0, 0.0);
}
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wire_extension_range_table Group
Use this group to specify the length of a wire extension where the wide wire spacing must
be observed. A wire extension is a piece of thin or fat metal extended out from a wide wire.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
wire_extension_range_table(template_name
id
) {
...
}
}
}
}
template_name
The name of a wire_lut_template defined at the phys_library level.
Example
wire_extension_range_table (wire_template_1) {
...
}
Complex Attributes
index_1
values
index_1 and values Complex Attributes
These attributes specify the wire width values and corresponding wire_extension_range
values.
Syntax
phys_library(library_name
id
) {
...
wire_extension_range_table (template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...);
values ("value
float
, value
float
, value
float
", "...", "...") ;
}
...
}
value, value, value, ...
Floating-point numbers.
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Example
wire_extension_range_table (wire_template_1) {
index_1 (0.4, 0.6, 0.8, 1.0);
values ( "0.1, 0.2, 0.3, 0.4" ) ;
}
routing_wire_model Group
A predefined routing wire ratio model that represents an estimation on interconnect
topology.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
}
}
}
model_name
Specifies the name of the predefined routing wire model.
Example
routing_wire_model(mod1) {
...
}
Simple Attributes
wire_length_x
wire_length_y
Complex Attributes
adjacent_wire_ratio
overlap_wire_ratio
wire_ratio_x
wire_ratio_y
wire_length_x Simple Attribute
The wire_length_x attribute specifies the estimated average horizontal wire length in the
direction for a net.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
wire_length_x :value
float
;
...
}
}
}
value
A floating-point number that represents the average horizontal length.
Example
wire_length_x : 305.4 ;
wire_length_y Simple Attribute
The wire_length_y attribute specifies the estimated average vertical wire lengths in the
direction for a net.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
wire_length_y : value
float
;
...
}
}
}
value
A floating-point number that represents the average vertical length.
Example
wire_length_y : 260.35 ;
adjacent_wire_ratio Complex Attribute
This attribute specifies the percentage of wiring on a layer that can run adjacent to wiring
on the same layer and still maintain the minimum spacing.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
adjacent_wire_ratio(value
float
, value
float
, ...) ;
...
}
}
}
value
Floating-point numbers that represent the percentage value. For
example, two parallel adjacent wires with the same length would have an
adjacent_wire_ratio value of 50.0 percent. For a library with n routing layers,
the adjacent_wire_ratio attribute has n floating values representing the ratio
on each routing layer.
Example
In the case of a library with four routing layers:
adjacent_wire_ratio(35.6, 2.41, 19.8, 25.3) ;
overlap_wire_ratio Complex Attribute
This attribute specifies the percentage of the wiring on the first layer that overlaps the
second layer.
The following syntax example shows the order for the 20 entries required for a library with
five routing layers.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
overlap_wire_ratio(
V_1_2
float
, V_1_3
float
, V_1_4
float
, V_1_5
float
,
V_2_1
float
, V_2_3
float
, V_2_4
float
, V_2_5
float
,
V_3_1
float
, V_3_2
float
, V_3_4
float
, V_3_5
float
,
V_4_1
float
, V_4_2
float
, V_4_3
float
, V_4_5
float
,
V_5_1
float
, V_5_2
float
, V_5_3
float
, V_5_4
float
) ;
...
}
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}
}
}
V_a_b
The overlap ratio that represents how much of the reference layer (a) is
overshadowed by another layer (b). The value of each V_a_b is a floating-point
number from 0 to 100.0. The sum of all V_a_n ratios must be less than or equal
to 100.0. The order of V_a_b is significant; it must be iteratively listed from the
routing layer closest to the substrate.
Example
In the case of a library with five routing layers:
overlap_wire_ratio( 5, 15.5, 7.5, 10, \
6.5, 16, 8.5, 10.5, \
15, 5.5, 5, 15.5, \
7.5, 10, 6.5, 16, \
8.5, 10.5, 15, 5.5) ;
wire_ratio_x Complex Attribute
The wire_ratio_x attribute specifies the percentage of total wiring in the horizontal
direction that you estimate to be on each layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
wire_ratio_x(value_1
float
, value_2
float
, value_3
float
, ...) ;
...
}
}
}
value_1, value_2, value_3, ...,
An array of floating-point numbers following the order of the routing layers,
starting from the one closest to the substrate. Each example is a floating-point
number value from 0 to 100.0. For example, if there are four routing layers, then
there are four floating-point numbers.
Note:
The sum of the floating-point numbers must be 100.0.
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Example
wire_ratio_x(25.0, 25.0, 25.0, 25.0) ;
wire_ratio_y Complex Attribute
The wire_ratio_y attribute specifies the percentage of total wiring in the vertical direction
that you estimate to be on each layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
routing_wire_model(model_name
id
) {
...
wire_ratio_y(value_1
float
, value_2
float
, value_3
float
, ...) ;
...
}
}
}
value_1, value_2, value_3, ...,
An array of floating-point numbers following the order of the routing layers,
starting from the one closest to the substrate. Each example is a floating-point
number value from 0 to 100.0. For example, if there are four routing layers, then
there are four floating-point numbers.
Note:
The sum of the floating-point numbers must be 100.0.
Example
wire_ratio_y(25.0, 25.0, 25.0, 25.0) ;
site Group
Defines the placement grid for macros.
Note:
Define a site group or a tile group, but not both.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
site(site_name
id
) {
...
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}
}
}
site_name
The name of the site.
Example
site(core) {
...
}
Simple Attributes
on_tile
site_class
symmetry
Complex Attribute
size
on_tile Simple Attribute
The on_tile attribute specifies an associated tile name.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
site(site_name
id
) {
on_tile : tile_name
id
)
...
}
}
}
tile_name
The name of the tile.
Example
on_tile : ;
site_class Simple Attribute
The site_class attribute specifies what type of devices can be placed on the site.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
site(site_name
id
) {
site_class : value
enum
;
...
}
}
}
value
Valid values are pad and core (default).
Example
site_class : pad ;
symmetry Simple Attribute
The symmetry attribute specifies the site symmetry. A site is considered asymmetrical,
unless explicitly specified otherwise.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
site(site_name
id
) {
symmetry : value
enum
;
...
}
}
}
where
value
Valid values are r, x, y, xy, and rxy.
x
Specifies symmetry about the x-axis
y
Specifies symmetry about the y-axis
r
Specifies symmetry in 90 degree counterclockwise rotation
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xy
Specifies symmetry about the x-axis and the y-axis
rxy
Specifies symmetry about the x-axis and the y-axis and in 90 degree
counterclockwise rotation increments
Example
symmetry : r ;
size Complex Attribute
The size attribute specifies the site dimension in normal orientation.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
site(site_name
id
) {
size(x_size
float
, y_size
float
) ;
...
}
}
}
x_size, y_size
Floating-point numbers that specify the bounding rectangle size. The bounding
rectangle size must be a multiple of the placement grid.
Example
size(0.9, 7.2) ;
tile Group
Use this group to define the placement grid for macros.
Note:
Define a site group or a tile group, but not both.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
tile (tile_name
id
) {
...
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}
}
}
tile_name
The name of the tile.
Simple Attribute
tile_class
Complex Attribute
size
tile_class Simple Attribute
The tile_class attribute specifies the tile class.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
tile(site_name
id
) {
tile_class : value
enum
;
...
}
}
}
value
Valid values are pad and core (default).
Example
tile_class : pad ;
size Complex Attribute
The size attribute specifies the site dimension in normal orientation.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
tile (site_name
id
) {
size(x_size
float
, y_size
float
) ;
...
}
}
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}
x_size, y_size
Floating-point numbers that specify the bounding rectangle size. The bounding
rectangle size must be a multiple of the placement grid.
Example
size(0.9, 7.2) ;
via Group
Use this group to specify a via. You can use the via group to specify vias with any number
of layers.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
...
}
}
}
via_name
The name of the via.
Example
via(via12) {
...
}
Simple Attributes
capacitance
inductance
is_default
is_fat_via
resistance
res_temperature_coefficient
top_of_stack_only
via_id
Groups
foreign
via_layer
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capacitance Simple Attribute
The capacitance attribute specifies the capacitance per cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
capacitance : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance value.
Example
capacitance : 0.2 ;
inductance Simple Attribute
The inductance attribute specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
inductance : value
float
;
...
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance : 0.5 ;
is_default Simple Attribute
The is_default attribute specifies the via as the default for the given layers.
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Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
is_default : value
Boolean
;
...
}
}
}
value
Valid values are TRUE and FALSE (default).
Example
is_default : TRUE ;
is_fat_via Simple Attribute
The is_fat_via attribute specifies that fat wire contacts are required when the wire width
is equal to or greater than the threshold specified. Specifies that this via is used by wide
wires
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
is_fat_via : value
Boolean
;
...
}
}
}
value
Valid values are TRUE and FALSE (default).
Example
is_fat_via : TRUE ;
resistance Simple Attribute
The resistance attribute specifies the aggregate resistance per contact rectangle.
Syntax
phys_library(library_name
id
) {
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resource(architecture
enum
) {
via(via_name
id
) {
resistance : value
float
;
...
}
}
}
value
A floating-point number that represents the resistance value.
Example
resistance : 0.0375 ;
res_temperature_coefficient Simple Attribute
This attribute specifies the coefficient of the first-order correction to the resistance per
square when the operating temperature does not equal the nominal temperature.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
value
A floating-point number that represents the coefficient.
Example
res_temperature_coefficient : 0.03 ;
top_of_stack_only Simple Attribute
This attribute specifies to use the via only on top of a via stack.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
top_of_stack_only : value
Boolean
;
...
}
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}
}
value
Valid values are TRUE and FALSE (default).
Example
top_of_stack_only : FALSE ;
via_id Simple Attribute
Use the via_id attribute to specify a number that identifies a device.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_id : value
int
;
...
}
}
}
value
Valid values are any integer between 1 and 255.
Example
via_id : 255 ;
foreign Group
Use this group to specify which GDSII structure (model) to use when placing an instance
of this via.
Note:
Only one foreign reference is allowed for each via.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
foreign(foreign_object_name
id
) {
...
}
}
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}
}
foreign_object_name
The name of the corresponding GDSII via (model).
Example
foreign(via34) {
...
}
Simple Attribute
orientation
Complex Attribute
origin
orientation Simple Attribute
The orientation attribute specifies how you place the foreign GDSII object.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
foreign(foreign_object_name
id
) {
orientation : value
enum
;
...
}
}
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 3.
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Figure 3 Orientation Examples
Example
orientation : FN ;
origin Complex Attribute
The origin attribute specifies the via origin with respect to the GDSII structure (model). In
the physical library, the origin of a via is its center; in GDSII, the origin is 0,0.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
foreign(foreign_object_name
id
) {
...
origin(num_x
float
, num_y
float
) ;
}
}
}
}
num_x, num_y
Numbers that specify the x- and y-coordinates.
Example
origin(-1, -1) ;
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via_layer Group
Use this group to specify layer geometries on one layer of the via.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
...
}
}
}
}
layer_name
Specifies the layer on which the geometries are located.
Example
via_layer(m1) {
...
}
Simple Attributes
max_wire_width
min_wire_width
Complex Attributes
contact_spacing
contact_array_spacing
enclosure
max_cuts
min_cuts
rectangle
rectangle_iterate
max_wire_width Simple Attribute
Use this attribute along with the min_wire_width attribute to define the range of wire
widths.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
max_wire_width : value
float
;
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...
}
}
}
}
value
A floating-point number representing the wire width.
Example
max_wire_width : 0.0 ;
min_wire_width Simple Attribute
Use this attribute along with the max_wire_width attribute to define the range of wire
widths.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
min_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the wire width.
Example
min_wire_width : 0.0 ;
contact_array_spacing Complex Attribute
This attribute specifies the edge-to-edge spacing on a contact layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
contact_array_spacing(value_x
float
, value_y
float
);
...
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}
}
}
}
value_x, value_y
Floating-point numbers that represent the horizontal and vertical spacing
between two abutting contact arrays.
Example
contact_array_spacing (0.0, 0.0) ;
contact_spacing Complex Attribute
The contact_spacing attribute specifies the center-to-center spacing for generating an
array of contact cuts in the via.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
contact_spacing(value_x
float
, value_y
float
);
...
}
}
}
}
x, y
Floating-point numbers that represent the spacing value in terms of the x
distance and y distance between the centers of two contact cuts.
Example
contact_spacing (0.0, 0.0) ;
enclosure Complex Attribute
The enclosure attribute specifies an enclosure on a metal layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
enclosure(value_x
float
, value_y
float
) ;
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...
}
}
}
}
value_x, value_y
Floating-point numbers that represent the enclosure.
Example
enclosure (0.0, 0.0) ;
max_cuts Complex Attribute
The max_cuts attribute specifies the maximum number of cuts on a contact layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
max_cuts(value_x
float
, value_y
float
) ;
...
}
}
}
}
value_x, value_y
Floating-point numbers that represent the maximum number of cuts in the
horizontal and vertical directions of a contact array.
Example
max_cuts (0.0, 0.0) ;
min_cuts Complex Attribute
The min_cuts attribute specifies the minimum number of neighboring cuts allowed within
a specified space (range).
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
min_cuts(value_x
float
, value_y
float
) ;
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...
}
}
}
}
value_x, value_y
Floating-point numbers that represent the minimum number of cuts in the
horizontal and vertical directions of a contact array.
Example
min_cuts (0.0, 0.0) ;
rectangle Complex Attribute
The rectangle attribute specifies a rectangular shape for the via.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
rectangle(x1
float
, y1
float
, x2
float
,
y2
float
) ;
...
}
}
}
}
x1, y1, x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangle.
Example
rectangle(-0.3. -0.3, 0.3, 0.3) ;
rectangle_iterate Complex Attribute
The rectangle_iterate attribute specifies an array of rectangles in a particular pattern.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via(via_name
id
) {
via_layer(layer_name
id
) {
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Syntax for Groups in the resource Group
rectangle_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
x1
float
, y1
float
, x2
float
, y2
float
)
...
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around the rectangles.
x1, y1; x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangles.
Example
rectangle_iterate(2, 2, 2.000, 4.000, 175.500, 1417.360,
176.500, 1419.140) ;
via_array_rule Group
Defines the specific via and minimum cut number for the different fat metal wire widths on
contact layer.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via_array_rule () {
...
}
}
}
Groups
min_cuts_table
reference_cut_table
min_cuts_table Group
Use this group to specify the values for the lookup table.
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Syntax for Groups in the resource Group
Note:
Only one foreign reference is allowed for each via.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via_array_rule () {
min_cuts_table (template_name
id
) {
...
}
}
}
}
template_name
The via_array_lut_template name.
Example
min_cuts_table (via34) {
...
}
Complex Attribute
index_1
index_2
values
index Complex Attribute
The index attribute specifies the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via_array_rule() {
min_cuts_table (template_name
id
) {
...
index(num_x
float
, num_y
float
) ;
}
}
}
}
num_x, num_y
Numbers that specify the x- and y-coordinates.
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Example
index (-1, -1) ;
reference_cut_table Group
Use this group to specify values for the lookup table.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via_array_rule () {
reference_cut_table (template_name
id
) {
...
}
}
}
}
template_name
The via_array_lut_template name.
Example
reference_cut_table (via34) {
...
}
Complex Attribute
index_1
index_2
values
index Complex Attribute
The index attribute specifies the default indexes.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
via_array_rule() {
reference_cut_table (template_name
id
) {
...
index(num_x
float
, num_y
float
) ;
}
}
}
}
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num_x, num_y
Numbers that specify the x- and y-coordinates.
Example
index (-1, -1) ;
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4
Specifying Attributes in the
topological_design_rules Group
You use the topological_design_rules group to specify the design rules for the
technology (such as minimum spacing and width).
The information in this chapter includes a description and syntax example for the attributes
that you can define within the topological_design_rules group.
Syntax for Attributes in the topological_design_rules Group
This chapter describes the attributes that you define in the topological_design_rules
group. The groups that you can define in the topological_design_rules group are
described in Chapter 5.
topological_design_rules Group
Defines all the design rules that apply to the physical library.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
...
}
}
Note:
A name is not required for the topological_design_rules group.
Example
topological_design_rules() {
...
}
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Syntax for Attributes in the topological_design_rules Group
Simple Attributes
antenna_inout_threshold
antenna_input_threshold
antenna_output_threshold
min_enclosed_area_table_surrounding_metal
Complex Attributes
contact_min_spacing
corner_min_spacing
diff_net_min_spacing
end_of_line_enclosure
min_enclosure
min_generated_via_size
min_overhang
same_net_min_spacing
Group
extension_wire_spacing_rule
antenna_inout_threshold Simple Attribute
Use this attribute to specify the default (maximum) threshold (cumulative) value for the
antenna effect on inout pins. Use this attribute for parameter-based calculations only; that
is, it is not required when your library contains an antenna_rule group.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_inout_threshold : value
float
;
...
}
}
value
A floating-point number that represents the global pin value.
Example
antenna_inout_threshold : 0.0 ;
antenna_input_threshold Simple Attribute
Use this attribute to specify the default (maximum) threshold (cumulative) value for the
antenna effect on input pins. Use this attribute for parameter-based calculations only; that
is, it is not required when your library contains an antenna_rule group.
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Syntax for Attributes in the topological_design_rules Group
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_input_threshold : value
float
;
...
}
}
value
A floating-point number that represents the global pin value.
Example
antenna_input_threshold : 0.0 ;
antenna_output_threshold Simple Attribute
Use this attribute to specify the default (maximum) threshold (cumulative) value for the
antenna effect on output pins. Use this attribute for parameter-based calculations only; that
is, it is not required when your library contains an antenna_rule group.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_output_threshold : value
float
;
...
}
}
value
A floating-point number that represents the global pin value.
Example
antenna_output_threshold : 0.0 ;
min_enclosed_area_table_surrounding_metal Simple Attribute
Use this attribute to specify the minimum enclosed area.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
min_enclosed_area_table_surrounding_metal(value
enum
) ;
...
}
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}
value
Valid values are all_fat_wires and at_least_one_fat_wire.
Example
min_enclosed_area_table_surrounding_metal : all_fat_wires;
contact_min_spacing Complex Attribute
The contact_min_spacing attribute specifies the minimum spacing required between two
different contact layers on different nets.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
contact_min_spacing(layer1_name
id
, layer2_name
id
, value
float
) ;
...
}
}
layer1_name, layer2_name
Specify the two contact layers. The layers can be equivalent or different.
value
A floating-point number that represents the spacing value.
Example
contact_min_spacing(cut01, cut12, 1)
corner_min_spacing Complex Attribute
The corner_min_spacing attribute specifies the spacing between two different contact
layers.
Note:
The corner_min_spacing simple attribute in the cont_layer group specifies
the minimum distance between two vias.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
corner_min_spacing(layer1_name
id
, layer2_name
id
, value
float
) ;
...
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}
}
layer1_name, layer2_name
Specify the two contact layers.
value
A floating-point number that represents the spacing value.
Example
corner_min_spacing () ;
end_of_line_enclosure Complex Attribute
The end_of_line_enclosure attribute defines an enclosure size to specify the end-of-line
rule for routing wire segments.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
end_of_line_enclosure(layer1_name
id
, layer2_name
id
, value
float
) ;
...
}
}
layer1_name, layer2_name
Specify the metal layer and a contact layer, respectively.
value
A floating-point number that represents the spacing value.
Example
end_of_line_enclosure () ;
min_enclosure Complex Attribute
The min_enclosure attribute defines the minimum distance at which a layer must enclose
another layer when the two layers overlap.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
min_enclosure(layer1_name
id
, layer2_name
id
, value
float
) ;
...
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}
}
layer1_name, layer2_name
Specify the metal layer and a contact layer, respectively.
value
A floating-point number that represents the spacing value.
Example
min_enclosure () ;
diff_net_min_spacing Complex Attribute
The diff_net_min_spacing attribute specifies the minimum spacing between a metal
layer and a contact layer.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
diff_net_min_spacing(layer1_name
id
, layer2_name
id
, value
float
) ;
...
}
}
layer1_name, layer2_name
Specify the metal layer and a contact layer, respectively.
value
A floating-point number that represents the spacing value.
Example
diff_net_min_spacing () ;
min_generated_via_size Complex Attribute
Use this attribute to specify the minimum size for the generated via. All edges of a via
must lie on the grid defined by the x- and y-coordinates.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
min_generated_via_size(num_x
float
, num_y
float
) ;
...
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}
}
num_x, num_y
Floating-point numbers that represent the minimum size for the x and y
dimensions.
Example
min_generated_via_size(0.01, 0.01) ;
min_overhang Complex Attribute
Use this attribute to specify the minimum overhang for the generated via.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
min_overhang(layer1
string
, layer2
string
, value
float
) ;
...
}
}
layer1, layer2
The names of the two overhanging layers.
value
A floating-point number that represents the minimum overhang value.
Example
min_overhang(0.01, 0.01) ;
same_net_min_spacing Complex Attribute
The same_net_min_spacing attribute specifies the minimum spacing required between
wires on a layer or on two layers in the same net.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
same_net_min_spacing(layer1_name
id
, layer2_name
id
, \
space
float
, is_stack
Boolean
) ;
...
}
}
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layer1_name, layer2_name
Specify the two routing layers, which can be different layers or the same layer.
space
A floating-point number representing the spacing value.
is_stack
Valid values are TRUE and FALSE. Set the value to TRUE to allow stacked vias at
the routing layer. When set to TRUE, the same_net_min_spacing value can be
0 (complete overlap) or the value held by the min_spacing attribute; otherwise
the value reflects the rule.
Example
same_net_min_spacing(m2, m2, 0.4, FALSE)
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5
Specifying Groups in the
topological_design_rules Group
You use the topological_design_rules group to specify the design rules for the
technology (such as minimum spacing and width).
This chapter describes the following groups:
•
antenna_rule Group
•
density_rule Group
• extension_wire_spacing_rule Group
•
stack_via_max_current Group
•
via_rule Group
• via_rule_generate Group
•
wire_rule Group
•
wire_slotting_rule Group
Syntax for Groups in the topological_design_rules Group
The following sections describe the groups you can define in the
topological_design_rules group:
antenna_rule Group
Use this group to specify the methods for calculating the antenna effect.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
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}
}
}
antenna_rule_name
The name of the antenna_rule group.
Example
antenna_rule (antenna_metal3_only) {
...description...
}
Simple Attributes
adjusted_gate_area_calculation_method
adjusted_metal_area_calculation_method
antenna_accumulation_calculation_method
antenna_ratio_calculation_method
apply_to
geometry_calculation_method
pin_calculation_method
routing_layer_calculation_method
Complex Attribute
layer_antenna_factor
Groups
adjusted_gate_area
adjusted_metal_area
antenna_ratio
metal_area_scaling_factor
adjusted_gate_area_calculation_method Simple Attribute
Use this attribute to specify a factor to apply to the gate area.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
adjusted_gate_area_calculation_method : value
enum
;
...
}
}
}
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value
Valid values are max_diffusion_area and total_diffusion_area.
Example
adjusted_gate_area_calculation_method :max_diffusion_area;
adjusted_metal_area_calculation_method Simple Attribute
Use this attribute to specify a factor to apply to the metal area.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
adjusted_metal_area_calculation_method : value
enum
;
...
}
}
}
value
Valid values are max_diffusion_area and total_diffusion_area.
Example
adjusted_metal_area_calculation_method :
max_diffusion_area ;
antenna_accumulation_calculation_method Simple Attribute
Use this attribute to specify a method for calculating the antenna.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
antenna_accumulation_calculation_method:value
enum
;
...
}
}
}
value
Valid values are single_layer, accumulative_ratio, and
accumulative_area.
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Example
antenna_accumulation_calculation_method : ;
antenna_ratio_calculation_method Simple Attribute
Use this attribute to specify a method for calculating the antenna.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
antenna_ratio_calculation_method : value
enum
;
...
}
}
}
value
Valid values are infinite_antenna_ratio, max_antenna_ratio, and
total_antenna_ratio.
Example
antenna_ratio_calculation_method : total_antenna_ratio ;
apply_to Simple Attribute
The apply_to attribute specifies the type of pin geometry that the rule applies to.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
apply_to : value
enum
;
...
}
}
}
value
The valid values are gate_area, gate_perimeter, and diffusion_area.
Example
apply_to : gate_area ;
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geometry_calculation_method Simple Attribute
Use this attribute with the pin_calculation_method attribute to specify which geometries
are applied to which pins. See Table 1 for a matrix of the options.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
geometry_calculation_method : value
enum
;
pin_calculation_method : value
enum
;
...
}
}
}
value
The valid values are all_geometries and connected_only.
Table 1 Calculating Geometries on Pins
geometry_calculation_method values
pin_calculation_method values
all_pins each_pin
all_geometries All the geometries are applied
to all pins. The connectivity
analysis is not performed.
Pins share antennas.
All the geometries of the net
are applied to every pin on the
net separately. The connectivity
analysis is not performed.
Antennas are not shared by
connected pins. This is the
most pessimistic calculation.
connected_only Considers connected
geometries as well as
sharing. This is the most
accurate calculation.
Only the geometries connected
to the pin are considered.
Sharing of antennas is not
allowed.
Example
geometry_calculation_method : connected_only ;
pin_calculation_method : all_pins ;
metal_area_scaling_factor_calculation_method Simple Attribute
Use this attribute to specify which diffusion area to use for scaling the metal area.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
metal_area_scaling_factor_calculation_method : value
enum
;
...
}
}
}
value
The valid values are max_diffusion_area and total_diffusion_area.
Example
metal_area_scaling_factor_calculation_method : total_diffusion_area ;
pin_calculation_method Simple Attribute
Use this attribute with the geometry_calculation_method attribute to specify which
geometries are applied to which pins. See Table 1 for a matrix of the options.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
geometry_calculation_method : value
enum
;
pin_calculation_method : value
enum
;
...
}
}
}
value
The valid values are all_pins and each_pin.
Example
geometry_calculation_method : connected_only ;
pin_calculation_method : all_pins ;
routing_layer_calculation_method Simple Attribute
Use this attribute to specify which property of the routing segments to use to calculate
antenna contributions.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
routing_layer_calculation_method : value
enum
;
...
}
}
}
value
The valid values are side_wall_area, top_area, side_wall_and_top_area,
segment_length, and segment_perimeter.
Example
routing_layer_calculation_method : top_area ;
layer_antenna_factor Complex Attribute
The layer_antenna_factor attribute specifies a factor in each routing or contact layer
that is multiplied to either the area or the length of the routing segments to determine their
contribution.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
(antenna_rule_name
id
) {
...
layer_antenna_factor(layer_name
string
, antenna_factor
float
) ;
...
}
}
}
layer_name
Specifies the layer that contains the factor.
antenna_factor
A floating-point number that represents the factor.
Example
layer_antenna_factor (m1_m2, 1) ;
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adjusted_gate_area Group
Use this group to specify gate area values.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
adjusted_gate_area(antenna_lut_template_name
id
) {
...
}
}
}
}
template_name
The name of the template.
Example
adjusted_gate_area () {
...description...
}
Complex Attributes
index_1
values
adjusted_metal_area Group
Use this group to specify metal area values.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
adjusted_metal_area(antenna_lut_template_name
id
) {
...
}
}
}
template_name
The name of the template.
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Example
adjusted_metal_area () {
...description...
}
Complex Attributes
index_1
values
antenna_ratio Group
Use this group to specify the piecewise linear table for antenna calculations.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
antenna_ratio (template_name
id
) {
...description...
}
}
}
}
Example
antenna_ratio (antenna_template_1) {
...
}
Complex Attributes
index_1
values
index_1 Complex Attribute
Use this optional attribute to specify, in ascending order, each diffusion area limit.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
antenna_ratio (template_name
id
) {
index_1(value
float
, value
float
, value
float
, ...) ;
...
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}
}
}
}
value, value, value, ...
Floating-point numbers that represent diffusion area limits in ascending order.
Example
antenna_ratio (antenna_template_1) {
index_1 ("0, 2.4, 4.8") ;
}
values Complex Attribute
The values attribute specifies the table ratio.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
antenna_ratio (template_name
id
) {
values (value
float
, value
float
, value
float
, ...) ;
}
}
}
}
value, value, value, ...
Floating-point numbers that represent the ratio to apply.
Example
antenna_ratio (antenna_template_1) {
values (10, 100, 1000) ;
}
Example 2 An antenna_rule Group
antenna_rule (antenna_metal3_only) {
apply_to : gate_area
geometry_calculation_method : connected_only
pin_calculation_method : all_pins ;
routing_layer_calculation_method : side_wall_area ;
layer_antenna_factor (m1_m2, 1) ;
antenna_ratio (antenna_template_1) {
values (10, 100, 1000) ;
}
metal_area_scaling_factor () {
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...
}
}
Example 2 shows the attributes and group in an antenna rule group.
metal_area_scaling_factor Group
Use this group to specify the piecewise linear table for antenna calculations.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
metal_area_scaling_factor (template_name
id
) {
...description...
}
}
}
}
Example
antenna_ratio (antenna_template_1) {
...
}
Complex Attributes
index_1
values
index_1 Complex Attribute
Use this optional attribute to specify, in ascending order, each diffusion area limit.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
antenna_ratio (template_name
id
) {
index_1(value
float
, value
float
, value
float
, ...) ;
...
}
}
}
}
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value, value, value, ...
Floating-point numbers that represent diffusion area limits in ascending order.
Example
antenna_ratio (antenna_template_1) {
index_1 ("0, 2.4, 4.8") ;
}
values Complex Attribute
The values attribute specifies the table ratio.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
antenna_rule(antenna_rule_name
id
) {
...
antenna_ratio (template_name
id
) {
values (value
float
, value
float
, value
float
, ...) ;
}
}
}
}
value, value, value, ...
Floating-point numbers that represent the ratio to apply.
Example
antenna_ratio (antenna_template_1) {
values (10, 100, 1000) ;
}
default_via_generate Group
Use the default_via_generate group to specify default horizontal and vertical layer
information.
Syntax
phys_library(library_nameid) {
topological_design_rules() {
default_via_generate ( name ) {
via_routing_layer( layer_name ) {
overhang ( float, float ); /*horizontal and vertical*/
end_of_line_overhang : float ;
}
via_contact_layer(layer_name) {
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rectangle ( float, float, float, float ) ;
resistance : float ;
}
}
...
density_rule Group
Use this group to specify the metal density rule for the layer.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
density_rule(routing_layer_name
id
) {
...
}
}
}
routing_layer_name
Example
density_rule () {
...
}
Complex Attributes
check_step
check_window_size
density_range
check_step Complex Attribute
The check_step attribute specifies the stepping distance in distance units.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
density_rule(routing_layer_name
id
) {
check_step (value_1
float
, value_2
float
)
...
}
}
}
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value_1, value_2
Floating-point numbers representing the stepping distance.
Example
check_step (0.0. 0.0);
check_window_size Complex Attribute
The check_window_size attribute specifies the check window dimensions.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
density_rule(routing_layer_name
id
) {
check_window_size (x_value
float
, y_value
float
)
...
}
}
}
x_value, y_value
Floating-point numbers representing the window size.
Example
check_window_size (0.5. 0.5);
density_range Complex Attribute
The density_range attribute specifies density percentages.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
density_rule(routing_layer_name
id
) {
density_range (min_value
float
, max_value
float
)
...
}
}
}
min_value, max_value
Floating-point numbers representing the minimum and maximum density
percentages.
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Example
density_range (0.0, 0.0);
extension_wire_spacing_rule Group
The extension_wire_spacing_rule group specifies the extension range for connected
wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
...
}
}
}
Example
extension_wire_spacing_rule() {
...
}
Groups
extension_wire_qualifier
min_total_projection_length_qualifier
spacing_check_qualifier
extension_wire_qualifier Group
The extension_wire_qualifier group defines an extension wire.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
...
}
}
}
}
Simple Attributes
connected_to_fat_wire
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corner_wire
not_connected_to_fat_wire
connected_to_fat_wire Simple Attribute
The connected_to_fat_wire attribute specifies whether a wire connected to a fat wire
within the fat wire’s extension range is an extension wire.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
connected_to_fat_wire : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
connected_to_fat_wire : ;
corner_wire Simple Attribute
The corner_wire attribute specifies whether a wire located in the corner of a fat wire’s
extension range is an extension wire.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
corner_wire : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
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Example
corner_wire : ;
not_connected_to_fat_wire Simple Attribute
The not_connected_to_fat_wire attribute specifies whether a wire that is not within a
fat wire’s extension range is an extension wire.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
not_connected_to_fat_wire : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
not_connected_to_fat_wire : ;
min_total_projection_length_qualifier Group
The min_total_projection_length_qualifier group defines the projection length.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
min_total_projection_length_qualifier () {
...
}
}
}
}
Simple Attributes
non_overlapping_projection
overlapping_projection
parallel_length
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non_overlapping_projection Simple Attribute
The non_overlapping_projection attribute specifies whether the extension wire
spacing rule includes the non-overlapping projection length between non-overlapping
extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
non_overlapping_projection : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
non_overlapping_projection : ;
overlapping_projection Simple Attribute
The overlapping_projection attribute specifies whether the extension wire spacing rule
includes the overlapping projection length between non-overlapping extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
overlapping_projection : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
overlapping_projection : ;
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parallel_length Simple Attribute
The parallel_length attribute specifies whether the extension wire spacing rule includes
the parallel length between extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
parallel_length : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
parallel_length : ;
spacing_check_qualifier Group
The spacing_check_qualifier group specifies...
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
spacing_check_qualifier () {
...
}
}
}
}
Simple Attributes
corner_to_corner
non_overlapping_projection_wire
overlapping_projection_wires
wires_to_check
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corner_to_corner Simple Attribute
The corner_to_corner attribute specifies whether the extension wire spacing rule
includes the corner-to-corner spacing between two extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
corner_to_corner : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
corner_to_corner : TRUE ;
non_overlapping_projection_wire Simple Attribute
The non-overlapping_projection_wire attribute specifies whether the extension wire
spacing rule includes the spacing between two non-overlapping extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
non_overlapping_projection_wire : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
non_overlapping_projection_wire : TRUE ;
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overlapping_projection_wires Simple Attribute
The overlapping_projection__wires attribute specifies whether the extension wire
spacing rule includes the spacing between two overlapping extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
overlapping_projection_wires : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE.
Example
overlapping_projection_wires : TRUE ;
wires_to_check Simple Attribute
The wires_to_check attribute specifies whether the extension wire spacing rule includes
the spacing between any two wires or only between extension wires.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
extension_wire_spacing_rule() {
extension_wire_qualifier () {
wires_to_check : value
enum
;
...
}
}
}
}
value
Valid values are all_wires and extension_wires.
Example
wires_to_check : all_wires ;
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stack_via_max_current Group
Use the stack_via_max_current group to define the values for current passing through a
via stack.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
}
}
}
name
Specifies a stack name.
Example
stack_via_max_current( ) {
...
}
Simple Attributes
bottom_routing_layer
top_routing_layer
Groups
max_current_ac_absavg
max_current_ac_avg
max_current_ac_peak
max_current_ac_rms
max_current_dc_avg
bottom_routing_layer Simple Attribute
The attribute specifies the bottom_routing_layer.
Syntax
phys_library(library_name
id
) {
...
topological_design_rules() {
stack_via_max_current (name
id
) {
...
bottom_routing_layer : layer_name
id
;
...
}
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}
}
}
layer_name
A string value representing the routing layer name.
Example
bottom_routing_layer : ;
top_routing_layer Simple Attribute
The top_routing_layer attribute specifies the top_routing_layer.
Syntax
phys_library(library_name
id
) {
...
topological_design_rules() {
stack_via_max_current (name
id
) {
...
top_routing_layer : layer_name
id
;
...
}
}
}
layer_name
A string value representing the routing layer name.
Example
top_routing_layer : ;
max_current_ac_absavg Group
Use this group to specify the absolute average value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
max_current_ac_absavg(template_name
id
) {
...
}
}
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}
}
template_name
The name of the contact layer.
Example
max_current_ac_absavg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_avg Group
Use this group to specify an average value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
max_current_ac_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_avg() {
...
}
Complex Attributes
index_1
index_2
index_3
values
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max_current_ac_peak Group
Use this group to specify a peak value for the AC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
max_current_ac_peak(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_ac_peak() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_ac_rms Group
Use this group to specify a root mean square value for the AC current that can pass
through a cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
max_current_ac_rms(template_name
id
) {
...
}
}
}
}
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template_name
The name of the contact layer.
Example
max_current_ac_rms() {
...
}
Complex Attributes
index_1
index_2
index_3
values
max_current_dc_avg Group
Use this group to specify an average value for the DC current that can pass through a cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
stack_via_max_current (name
id
) {
...
max_current_dc_avg(template_name
id
) {
...
}
}
}
}
template_name
The name of the contact layer.
Example
max_current_dc_avg() {
...
}
Complex Attributes
index_1
index_2
values
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via_rule Group
Use this group to define vias used at the intersection of special wires. You can have
multiple via_rule groups for a given layer pair.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule(via_rule_name
id
) {
...
}
}
}
via_rule_name
Specifies a via rule name.
Example
via_rule(crossm1m2) {
...
}
Simple Attribute
via_list
Group
routing_layer_rule
via_list Simple Attribute
The via_list attribute specifies a list of vias. The router selects the first via that satisfies
the routing layer rules.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule(via_rule_name
id
) {
via_list : "via_name1
id
;
...
}
}
}
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via_name1, ..., via_nameN
Specify the via values used in the selection process.
Example
via_list : "via12, via23" ;
routing_layer_rule Group
Use this group to specify the criteria for selecting a via from a list you specify with the vias
attribute.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
...
}
}
}
}
layer_name
Specifies the name of a routing layer that the via connects to.
Example
routing_layer_rule(metal1) {
...
}
Simple Attributes
contact_overhang
max_wire_width
min_wire_width
metal_overhang
routing_direction
contact_overhang Simple Attribute
The contact_overhang attribute specifies the amount of metal (wire) between a contact
and a via edge in the specified routing direction on all routing layers.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
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via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
contact_overhang : value
float
;
...
}
}
}
}
value
A floating-point number that represents the value of the overhang.
Example
contact_overhang : 9.000e-02 ;
max_wire_width Simple Attribute
Use this attribute along with the min_wire_width attribute to define the range of wire
widths subject to these via rules.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
max_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number that represents the value for the maximum wire width.
Example
max_wire_width : 1.2 ;
min_wire_width Simple Attribute
Use this attribute along with the max_wire_width attribute to define the range of wire
widths subject to these via rules.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
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via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
min_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number that represents the value for the minimum wire width.
Example
min_wire_width : 0.4 ;
metal_overhang Simple Attribute
The metal_overhang attribute specifies the amount of metal (wire) at the edges of wire
intersection on all routing layers of the via_rule in the specified routing direction.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
metal_overhang : value
float
;
...
}
}
}
}
value
A floating-point number that represents the value of the overhang.
Example
metal_overhang : 0.0 ;
routing_direction Simple Attribute
The routing_direction attribute specifies the preferred routing direction for metal that
extends to make the overhang and metal overhang on all routing layers.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
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via_rule(via_rule_name
id
) {
routing_layer_rule(layer_name
id
) {
routing_direction : value
enum
;
...
}
}
}
}
value
Valid values are horizontal and vertical.
Example
routing_direction : horizontal ;
via_rule_generate Group
Use this group to specify the formula for generating vias when they are needed in the case
of special wiring. You can have multiple via_rule_generate groups for a given layer pair.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
...
}
}
}
via_rule_generate_name
The name for the via_rule_generate group.
Example
via_rule_generate(via12gen) {
...
}
Simple Attributes
capacitance
inductance
resistance
res_temperature_coefficient
Groups
contact_formula
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routing_layer_formula
capacitance Simple Attribute
The capacitance attribute specifies the capacitance per cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_name
id
) {
capacitance : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance value.
Example
capacitance : 0.02 ;
inductance Simple Attribute
The inductance attribute specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_name
id
) {
inductance : value
float
;
...
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance : 0.03 ;
resistance Simple Attribute
The resistance attribute specifies the aggregate resistance per contact rectangle.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_name
id
) {
resistance : value
float
;
...
}
}
}
value
A floating-point number that represents the resistance value.
Example
resistance : 0.0375 ;
res_temperature_coefficient Simple Attribute
The res_temperature_coefficient attribute specifies the first-order correction to
the resistance per square when the operating temperature does not equal the nominal
temperature.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
value
A floating-point number that represents the coefficient.
Example
res_temperature_coefficient : 0.0375 ;
contact_formula Group
Use this group to specify the contact-layer geometry-generation formula for the generated
via.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
) {
...
}
}
}
}
contact_layer_name
The name of the associated contact layer.
Example
contact_formula(cut23) {
...
}
Simple Attributes
max_cut_rows_current_direction
min_number_of_cuts
resistance
routing_direction
Complex Attributes
contact_array_spacing
contact_spacing
max_cuts
rectangle
max_cut_rows_current_direction Simple Attribute
Use this attribute to specify the maximum number of rows of cuts, in the current routing
direction, in a non-turning via for global wire (power and ground).
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
)
max_cut_rows_current_direction : value
int
;
...
}
}
}
}
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value
An integer representing the maximum number of rows of cuts in a via.
Example
max_cut_rows_current_direction : 3 ;
min_number_of_cuts Simple Attribute
Use this attribute to specify attribute specifies the minimum number of cuts.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
)
min_number_of_cuts : value
int
;
...
}
}
}
}
value
An integer representing the minimum number of cuts.
Example
min_number_of_cuts : 2;
resistance Simple Attribute
The resistance attribute specifies the aggregate resistance per contact cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
)
resistance : value
float
;
...
}
}
}
}
value
A floating-point number representing the aggregate resistance.
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Example
resistance : 1.0 ;
routing_direction Simple Attribute
The routing_direction attribute specifies the preferred routing direction, which serves
as the direction of extension for contact_overlap and metal_overhang on all of the
generated via routing layers.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
routing_direction : value
enum
;
...
}
}
}
}
value
Valid values are horizontal and vertical.
Example
routing_direction : vertical ;
contact_array_spacing Complex Attribute
The contact_array attribute specifies the spacing between two contact arrays.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
) {
contact_array_spacing(x
float
, y
float
) ;
...
}
}
}
}
x, y
Floating-point numbers that represent the spacing value.
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Example
contact_array_spacing( 0.0 ) ;
contact_spacing Complex Attribute
The contact_spacing attribute specifies the center-to-center spacing for generating an
array of contact cuts in the generated via.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
) {
contact_spacing(x
float
, y
float
) ;
...
}
}
}
}
x, y
Floating-point numbers that represent the spacing value in terms of the x
distance and y distance between the centers of two contact cuts.
Example
contact_spacing(0.84, 0.84) ;
max_cuts Complex Attribute
The max_cuts attribute specifies the maximum number of cuts.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
) {
max_cuts(x
int
, y
int
) ;
...
}
}
}
}
x, y
Integer numbers that represent the number of cuts.
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Example
max_cuts () ;
rectangle Complex Attribute
The rectangle attribute specifies the dimension of the contact cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
contact_formula(contact_layer_name
id
) {
rectangle(x1
float
, y1
float
, x2
float
, y1
float
) ;
...
}
}
}
}
x1, y1, x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangle.
Example
rectangle(-0.3, -0.3, 0.3, 0.3) ;
routing_formula Group
Use this group to specify properties for the routing layer. You must specify a
routing_formula group for each routing layer associated with a via; typically, two routing
layers are associated with a via.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
...
}
}
}
}
layer_name
The name of the associated routing layer.
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Example
routing_formula(metal1) {
...
}
routing_formula(metal2) {
...
}
Simple Attributes
contact_overhang
max_wire_width
min_wire_width
metal_overhang
routing_direction
Complex Attribute
contact_overhang Simple Attribute
The contact_overhang attribute specifies the minimum amount of metal (wire) extension
between a contact and a via edge in the specified direction.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
contact_overhang : value
float
;
...
}
}
}
}
value
A floating-point number representing the amount of contact overhang.
Example
contact_overhang : 9.000e-01 ;
max_wire_width Simple Attribute
Use this attribute along with the min_wire_width attribute to define the range of wire
widths subject to these via generation rules.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
max_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the maximum wire width.
Example
max_wire_width : 2.4 ;
min_wire_width Simple Attribute
Use this attribute along with the max_wire_width attribute to define the range of wire
widths subject to these via generation rules.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
min_wire_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the minimum wire width.
Example
min_wire_width : 1.4 ;
metal_overhang Simple Attribute
The metal_overhang attribute specifies the minimum amount of metal overhang at the
edges of wire intersections in the specified direction.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
metal_overhang : value
float
;
...
}
}
}
}
value
A floating-point number representing the amount of metal overhang.
Example
metal_overhang : 0.1 ;
routing_direction Simple Attribute
The routing_direction attribute specifies the preferred routing direction, which serves
as the direction of extension for contact_overlap and metal_overhang on all of the
generated via routing layers.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
routing_direction : value
enum
;
...
}
}
}
}
value
Valid values are horizontal and vertical.
Example
routing_direction : vertical ;
enclosure Complex Attribute
The enclosure attribute specifies the dimensions of the routing layer enclosures.
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Syntax for Groups in the topological_design_rules Group
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
via_rule_generate(via_rule_generate_name
id
) {
routing_formula(layer_name
id
) {
enclosure(value_1
float
, value_2
float
)
...
}
}
}
}
value_1, value_2
Floating-point number representing the enclosure dimensions.
Example
enclosure (0.0, 0.0) ;
wire_rule Group
Use this group to specify the nondefault wire rules for regular wiring.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
...
}
}
}
wire_rule_name
The name of the wire rule group.
Example
wire_rule(rule1) {
...
}
Groups
layer_rule
via
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layer_rule Group
Use this group to specify properties for each routing layer. The width and spacing
specifications in this group override the default values defined in the routing_layer
group in the resource group. If the extension is not specified or if the extension has a
nonzero value less than half the routing width, then a default extension of half the routing
width for the layer is used.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
layer_rule(layer_name
id
) {
...
}
}
}
}
layer_name
The name of the layer defined in the wire rule.
Example
layer_rule(metal1) {
...
}
Simple Attributes
min_spacing
wire_extension
wire_width
Complex Attribute
same_net_min_spacing
min_spacing Simple Attribute
The min_spacing attribute specifies the minimum spacing for regular wires that are on the
specified layer, subject to the wire rule, and belonging to different nets.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
layer_rule(layer_name
id
) {
min_spacing : value
float
;
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...
}
}
}
}
value
A floating-point number representing the spacing value.
Example
min_spacing : 0.4 ;
wire_extension Simple Attribute
The wire_extension attribute specifies a default distance value for extending wires at
vias for regular wires on this layer subject to the wire rule. A value of 0 indicates no wire
extension. If the value is less than half the wire_width value, the router uses half the
value of the wire_width attribute as the wire extension value. If the wire_width attribute
is not defined, the router uses the default value declared in the routing_layer group.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
layer_rule(layer_name
id
) {
wire_extension : value
float
;
...
}
}
}
}
value
A floating-point number that represents the wire extension value.
Example
wire_extension : 0.25 ;
wire_width Simple Attribute
The wire_width attribute specifies the wire width for regular wires that are on the
specified layer and are subject to the wire rule. The wire_width value must be equivalent
to or more than the default_wire_width value defined in the layer group.
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Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
layer_rule(layer_name
id
) {
wire_width : value
float
;
...
}
}
}
}
value
A floating-point number representing the width value.
Example
wire_width : 0.4 ;
same_net_min_spacing Complex Attribute
The same_net_min_spacing attribute specifies the minimum spacing required between
wires on a layer or on two layers in the same net.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
layer_rule(layer_name
id
) {
...
same_net_min_spacing(layer1_name
id
,
layer2_name
id
, space
float
, is_stack
Boolean
) ;
}
}
}
}
layer1_name, layer2_name
Specify two routing layers. To specify spacing between wires on the same layer,
use the same name for both layer1_name and layer2_name.
space
A floating-point number representing the minimum spacing.
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is_stack
Valid values are TRUE and FALSE. Set the value to TRUE to allow stacked vias at
the routing layer. When set to TRUE, the same_net_min_spacing value can be
0 (complete overlap) or the value held by the min_spacing attribute.
Example
same_net_min_spacing(m2, m2, 0.4, false);
via Group
Use this group to specify the via that the router uses for this wire rule.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
...
}
}
}
}
via_name
Specifies the via name.
Example
via(non_default_via12) {
...
}
Simple Attributes
capacitance
inductance
res_temperature_coefficient
resistance
Complex Attribute
same_net_min_spacing
Groups
foreign
via_layer
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capacitance Simple Attribute
The capacitance attribute specifies the capacitance per cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
capacitance : value
float
;
...
)
}
}
}
value
A floating-point number that represents the capacitance per cut.
Example
capacitance : 0.2 ;
inductance Simple Attribute
The inductance attribute specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
inductance : value
float
;
...
}
}
}
}
value
A floating-point number that represents the inductance per cut.
Example
inductance : 0.03 ;
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res_temperature_coefficient Simple Attribute
Use this attribute to specify the first-order temperature coefficient for the resistance.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
}
value
A floating-point number that represents the temperature coefficient.
Example
res_temperature_coefficient : 0.0375 ;
resistance Simple Attribute
The resistance attribute specifies the aggregate resistance per contact cut.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
resistance : value
float
;
...
}
}
}
}
value
A floating-point number representing the resistance.
Example
resistance : 1.000e+00 ;
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same_net_min_spacing Complex Attribute
The same_net_min_spacing attribute specifies the minimum spacing required between
wires on a layer or on two layers in the same net.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
...
same_net_min_spacing(layer1_name
id
,
layer2_name
id
, space
float
, is_stack
Boolean
) ;
}
}
}
}
layer1_name, layer2_name
Specify two routing layers. To specify spacing between wires on the same layer,
use the same name for both layer1_name and layer2_name.
space
A floating-point number representing the minimum spacing.
is_stack
Valid values are TRUE and FALSE. Set the value to TRUE to allow stacked vias at
the routing layer. When set to TRUE, the same_net_min_spacing value can be
0 (complete overlap) or the value held by the min_spacing attribute.
Example
same_net_min_spacing(m2, m2, 0.4, false);
foreign Group
The foreign attribute specifies which GDSII structure (model) to use when an instance of
a via is placed.
Note:
Only one foreign group is allowed for each via.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
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foreign(foreign_object_name
id
) {
...
}
}
}
}
}
foreign_object_name
The name of a GDSII structure (model).
Example
foreign(fdesf2a6) {
...
}
Simple Attribute
orientation
Complex Attribute
origin
orientation Simple Attribute
The orientation attribute specifies the orientation of a foreign object.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
foreign(foreign_object_name
id
) {
orientation : value
enum
;
...
}
}
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 4.
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Figure 4 Orientation Examples
Example
orientation : FN ;
origin Complex Attribute
The origin attribute specifies the equivalent coordinates for the origin of a placed foreign
object.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
foreign(foreign_object_name
id
) {
...
origin(num_x
float
, num_y
float
) ;
}
}
}
}
}
num_x, num_y
Floating-point numbers that specify the coordinates where the foreign object is
placed.
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Example
origin(-1, -1) ;
via_layer Group
Use this group to specify a via layer. A via can have one or more via_layer groups.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
via_layer(via_layer
id
) {
...
}
}
}
}
}
via_layer
A predefined layer name.
Example
via_layer(via23) {
...
}
Complex Attribute
rectangle
rectangle Complex Attribute
The rectangle attribute specifies the geometry of the via on the layer.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_rule(wire_rule_name
id
) {
via(via_name
id
) {
via_layer(via_layer
id
) {
rectangle(x1
float
, y1
float
, x2
float
, y2
float
) ;
...
}
}
}
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}
}
x1, y1, x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangle.
Example
rectangle(-0.3, -0.3, 0.3, 0.3) ;
wire_slotting_rule Group
Use this group to specify the wire slotting rules to satisfy the maximum metal density
design rule.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
...
}
}
}
Simple Attributes
max_metal_density
min_length
min_width
Complex Attributes
slot_length_range
slot_length_side_clearance
slot_length_wise_spacing
slot_width_range
slot_width_side_clearance
slot_width_wise_spacing
max_metal_density Simple Attribute
Use this attribute to specify the maximum metal density for a slotted layer, as a percentage
of the layer.
Syntax
phys_library(library_name
id
) {
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topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
max_metal_density : value
float
;
}
}
}
value
A floating-point number that represents the percentage.
Example
max_metal_density : 0.70 ;
min_length Simple Attribute
The min_length attribute specifies the the minimum geometry length threshold that
triggers slotting. Slotting is triggered when the thresholds specified by the min_length and
min_width attributes are both surpassed.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
min_length : value
float
;
}
}
}
value
A floating-point number that represents the minimum geometry length threshold.
Example
min_length : 0.5 ;
min_width Simple Attribute
The min_width attribute specifies the the minimum geometry length threshold that
triggers slotting. Slotting is triggered when the thresholds specified by the min_length and
min_width attributes are both surpassed.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
min_width : value
float
;
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}
}
}
value
A floating-point number that represents the minimum geometry width threshold.
Example
min_width : 0.4 ;
slot_length_range Complex Attribute
The slot_length attribute specifies the allowable range for the length of a slot.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
slot_length_range (min_value
float
, max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum range values.
Example
slot_length_range (0.2, 0.3) ;
slot_length_side_clearance Complex Attribute
Use this attribute to specify the spacing from the end edge of a wire to its outermost slot.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
slot_length_side_clearance (min_value
float
, max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum spacing
values.
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Example
slot_length_side_clearance (0.2, 0.4) ;
slot_length_wise_spacing Complex Attribute
Use this attribute to specify the minimum spacing between adjacent slots in a direction
perpendicular to the wire (current flow) direction.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
slot_length_wise_spacing(min_value
float
, max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum spacing
distance values.
Example
slot_length_wise_spacing (0.2, 0.3);
slot_width_range Complex Attribute
Use this attribute to specify the allowable range for the width of a slot.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
slot_width_range(min_value
float
, max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum range values.
Example
slot_width_range (0.2, 0.3) ;
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slot_width_side_clearance Complex Attribute
Use this attribute to specify the spacing from the side edge of a wire to its outermost slot.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
) {
slot_width_side_clearance(min_value
float
,
max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum spacing
distance values.
Example
slot_width_side_clearance (0.2, 0.3) ;
slot_width_wise_spacing Complex Attribute
Use this attribute to specify the minimum spacing between slots in a direction
perpendicular to the wire (current flow) direction.
Syntax
phys_library(library_name
id
) {
topological_design_rules() {
wire_slotting_rule(routing_layer_name
id
){
slot_width_wise_spacing (min_value
float
,
max_value
float
) ;
}
}
}
min_value, max_value
Floating-point numbers that represent the minimum and maximum spacing
distance values.
Example
slot_width_wise_spacing (0.2, 0.3) ;
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Specifying Attributes and Groups in the
process_resource Group
You use the process_resource group to specify various process corners in a particular
process. The process_resource group is defined inside the phys_library group and
must be defined before you model any cell. Multiple process_resource groups are
allowed in a physical library.
The information in this chapter includes the following:
•
Syntax for Attributes in the process_resource Group
•
Syntax for Groups in the process_resource Group
Syntax for Attributes in the process_resource Group
This section describes the attributes that you define in the process_resource group.
Simple Attributes
baseline_temperature
field_oxide_thickness
process_scale_factor
Complex Attribute
plate_cap
baseline_temperature Simple Attribute
Defines a baseline operating condition temperature.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
...
baseline_temperature : value
float
;
...
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}
}
value
A floating-point number representing the baseline temperature.
Example
baseline_temperature : 0.5 ;
field_oxide_thickness Simple Attribute
Specifies the field oxide thickness.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
...
field_oxide_thickness : value
float
;
...
}
}
value
A positive floating-point number in distance units.
Example
field_oxide_thickness : 0.5 ;
process_scale_factor Simple Attribute
Specifies the factor to describe the process shrinkage factor to scale the length, width, and
spacing geometries.
Note:
Do not specify a value for the process_scale_factor attribute if you specify a
value for the shrinkage attribute or shrinkage_table group.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
...
process_scale_factor : value
float
;
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...
}
}
value
A floating-point number representing the scaling factor.
Example
process_scale_factor : 0.96 ;
plate_cap Complex Attribute
Specifies the interlayer capacitance per unit area when a wire on the first routing layer
overlaps a wire on the second routing layer.
Note:
The plate_cap statement must follow all the routing_layer statements and
precede the routing_wire_model statements.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
...
routing_layer(layer_name
id
) {
...
}
plate_cap(PCAP_l1_l2
float
, PCAP_l1_l3
float
,
PCAP_ln-1_ln
float
) ;
routing_wire_model(model_name
id
) {
...
}
}
}
PCAP_la_lb
Represents a floating-point number that specifies the plate capacitance per
unit area between two routing layers, layer a and layer b. The number of PCAP
values is determined by the number of previously defined routing layers. You
must specify every combination of routing layer pairs based on the order of the
routing layers. For example, if the layers are defined as substrate, layer1, layer2,
and layer3, then the PCAP values are defined in PCAP_l1_l2, PCAP_l1_l3, and
PCAP_l2_l3.
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Example
The example shows a plate_cap statement for a library with four layers. The values are
indexed by the routing layer order.
plate_cap( 0.35, 0.06, 0.0, 0.25, 0.02, 0.15) ;
/* PCAP_1_2, PCAP_1_3, PCAP_1_4, PCAP_2_3, PCAP_2_4, PCAP_3_4 */
Syntax for Groups in the process_resource Group
This section describes the groups that you define in the process_resource group.
Groups
process_cont_layer
process_routing_layer
process_via
process_via_rule_generate
process_wire_rule
process_cont_layer Group
Specifies values for the process contact layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_cont_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the contact layer.
Example
process_cont_layer(m1) {
...
}
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process_routing_layer Group
Use a process_routing_layer group to define operating-condition-specific routing layer
attributes.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
...
}
}
}
layer_name
The name of the scaled routing layer.
Example
process_routing_layer(m1) {
...
}
Simple Attributes
cap_multiplier
cap_per_sq
coupling_cap
edgecapacitance
fringe_cap
height
inductance_per_dist
lateral_oxide_thickness
oxide_thickness
res_per_sq
shrinkage
thickness
Complex Attributes
conformal_lateral_oxide
lateral_oxide
Groups
resistance_table
shrinkage_table
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cap_multiplier Simple Attribute
Specifies a scaling factor for interconnect capacitance to account for changes in
capacitance due to nearby wires.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
cap_multiplier : value
float
;
...
}
}
}
value
A floating-point number representing the scaling factor.
Example
cap_multiplier : 2.0
cap_per_sq Simple Attribute
Specifies the substrate capacitance per square unit area of a process routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
cap_per_sq : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance for a square unit of wire,
in picofarads per square distance unit.
Example
cap_per_sq : 5.909e-04 ;
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coupling_cap Simple Attribute
Specifies the coupling capacitance per unit length between parallel wires on the same
layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
coupling_cap : value
float
;
...
}
}
}
value
A floating-point number that represents the coupling capacitance.
Example
coupling_cap: 0.000019 ;
edgecapacitance Simple Attribute
Specifies the total peripheral capacitance per unit length of a wire on the process routing
layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
edgecapacitance : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance per unit length value.
Example
edgecapacitance : 0.00065 ;
fringe_cap Simple Attribute
Specifies the fringe (sidewall) capacitance per unit length of a process routing layer.
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Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
fringe_cap : value
float
;
...
}
}
}
value
A floating-point number that represents the fringe capacitance.
Example
fringe_cap : 0.00023 ;
height Simple Attribute
Specifies the distance from the top of the substrate to the bottom of the routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
height : value
float
;
...
}
}
}
value
A floating-point number representing the distance unit of measure.
Example
height : 1.0 ;
inductance_per_dist Simple Attribute
Specifies the inductance per unit length of a process routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
inductance_per_dist : value
float
;
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...
}
}
}
value
A floating-point number that represents the inductance.
Example
inductance_per_dist : 0.0029 ;
lateral_oxide_thickness Simple Attribute
Specifies the lateral oxide thickness for the layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
){
process_routing_layer(layer_name
id
) {
lateral_oxide_thickness : value
float
;
...
}
}
}
value
A floating-point number that represents the lateral oxide thickness.
Example
lateral_oxide_thickness : 1.33 ;
oxide_thickness Simple Attribute
Specifies the oxide thickness for the layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
){
process_routing_layer(layer_name
id
) {
oxide_thickness : value
float
;
...
}
}
}
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value
A floating-point number that represents the oxide thickness.
Example
oxide_thickness : 1.33 ;
res_per_sq Simple Attribute
Specifies the substrate resistance per square unit area of a process routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
res_per_sq : value
float
;
...
}
}
}
value
A floating-point number representing the resistance.
Example
res_per_sq : 1.200e-01 ;
shrinkage Simple Attribute
Specifies the total distance by which the wire width on the layer shrinks or expands.
The shrinkage parameter is a sum of the shrinkage for each side of the wire. The post-
shrinkage wire width represents the final processed silicon width as calculated from the
drawn silicon width in the design database.
Note:
Do not specify a value for the shrinkage attribute or shrinkage_table group if
you specify a value for the process_scale_factor attribute.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
shrinkage : value
float
;
...
}
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}
}
value
A floating-point number representing the distance unit of measure. A positive
number represents shrinkage; a negative number represents expansion.
Example
shrinkage : 0.00046 ;
thickness Simple Attribute
Specifies the thickness of the user units of objects process routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
thickness : value
float
;
...
}
}
}
value
A floating-point number representing the thickness of the routing layer.
Example
thickness : 0.02 ;
conformal_lateral_oxide Complex Attribute
Specifies the substrate capacitance per unit area of a process routing layer.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
conformal_lateral_oxide : value
float
;
...
}
}
}
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value
A floating-point number that represents the capacitance for a square unit of wire,
in picofarads per square distance unit.
Example
conformal_lateral_oxide : 5.909e-04 ;
lateral_oxide Complex Attribute
Specifies the lateral oxide thickness.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
lateral_oxide : value
float
;
...
}
}
}
value
A floating-point number representing the lateral oxide thickness.
Example
lateral_oxide : 5.909e-04
resistance_table Group
Use this group to specify an array of values for sheet resistance.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
resistance_table(template_name
id
) {
...
}
}
}
}
Example
resistance_table ( ) {
...
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}
Complex Attributes
index_1
index_2
values
index_1 and index_2 Complex Attributes
Specifies the default indexes.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
resistance_table(template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...)
index_2 (value
float
, value
float
, value
float
, ...)
}
}
}
}
Example
resistance_table (template_name) {
index_1 ( ) ;
index_2 ( ) ;
values ( ) ;
shrinkage_table Group
Specifies a lookup table template.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_routing_layer(layer_name
id
) {
shrinkage_table(template_name
id
) {
...
}
}
}
}
template_name
The name of a shrinkage_lut_template defined at the phys_library level.
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Example
shrinkage_table (shrinkage_template_1) {
...
}
Complex Attributes
index_1
index_2
values
index_1 and index_2 Complex Attributes
Specify the default indexes.
Syntax
phys_library(library_name
id
) {
...
shrinkage_table (template_name
id
) {
index_1 (value
float
, value
float
, value
float
, ...);
index_2 (value
float
, value
float
, value
float
, ...);
...
}
...
}
value, value, value, ...
Floating-point numbers that represent the default indexes.
Example
shrinkage_lut_template (resistance_template_1) {
index_1 (0.0, 0.0, 0.0, 0.0);
index_2 (0.0, 0.0, 0.0, 0.0);
}
process_via Group
Use a process_via group to define an operating-condition-specific resistance value for a
via.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via(via_name
id
) {
...
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}
}
}
via_name
The name of the via.
Example
via(via12) {
...
}
Simple Attributes
capacitance
inductance
resistance
res_temperature_coefficient
capacitance Simple Attribute
Specifies the capacitance contact in a cell instance (or over a macro).
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via(via_name
id
) {
capacitance : value
float
;
...
}
}
}
value
A floating-point number that represents the capacitance.
Example
capacitance : 0.05 ;
inductance Simple Attribute
Specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
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process_via(via_name
id
) {
inductance : value
float
;
...
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance : 0.03 ;
resistance Simple Attribute
Specifies the aggregate resistance per contact rectangle.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via(via_name
id
) {
resistance : value
float
;
...
}
}
}
value
A floating-point number that represents the resistance value.
Example
resistance : 0.0375 ;
res_temperature_coefficient Simple Attribute
The res_temperature_coefficient attribute specifies the coefficient of the first-order
correction to the resistance per square when the operating temperature does not equal the
nominal temperature.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via(via_name
id
) {
res_temperature_coefficient : value
float
;
...
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}
}
}
value
A floating-point number that represents the temperature coefficient.
Example
res_temperature_coefficient : 0.03 ;
process_via_rule_generate Group
Use a process_via_rule_generate group to define an operating-condition-specific
resistance value for a via.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via_rule_generate(via_name
id
) {
...
}
}
}
via_name
The name of the via.
Example
via(via12) {
...
}
Simple Attributes
capacitance
inductance
resistance
res_temperature_coefficient
capacitance Simple Attribute
Specifies the capacitance per cut.
Syntax
phys_library(library_name
id
) {
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process_resource(architecture
enum
) {
process_via_rule_generate(via_name
id
) {
capacitance : value
enum
;
...
}
}
}
value
A floating-point number that represents the capacitance value.
Example
capacitance : 0.05 ;
inductance Simple Attribute
Specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via_rule_generate(via_name
id
) {
inductance : value
float
;
...
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance : 0.03 ;
resistance Simple Attribute
Specifies the aggregate resistance per contact rectangle.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via_rule_generate(via_name
id
) {
resistance : value
float
;
...
}
}
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}
value
A floating-point number that represents the resistance.
Example
resistance : 0.0375 ;
res_temperature_coefficient Simple Attribute
Specifies the first-order temperature coefficient for the resistance.
Syntax
phys_library(library_name
id
) {
process_resource(architecture
enum
) {
process_via_rule_generate(via_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
value
A floating-point number that represents the temperature coefficient.
Example
res_temperature_coefficient : 0.0375 ;
process_wire_rule Group
Use this group to define an operating-condition-specific value for a nondefault regular via
defined within a wire_rule group.
Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
...
}
}
}
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wire_rule_name
The name of the wire rule group.
Example
process_wire_rule(rule1) {
...
}
Group
process_via
process_via Group
Specifies the via that the router uses for this wire rule.
Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
...
}
}
}
}
via_name
Specifies the via name.
Example
process_via(non_default_via12) {
...
}
Simple Attributes
capacitance
inductance
resistance
res_temperature_coefficient
capacitance Simple Attribute
Specifies the capacitance per cut.
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Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
capacitance : value
enum
;
...
}
}
}
}
value
A floating-point number that represents the capacitance value.
Example
capacitance : 0.0 ;
inductance Simple Attribute
Specifies the inductance per cut.
Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
inductance : value
float
;
...
}
}
}
}
value
A floating-point number that represents the inductance value.
Example
inductance : 0.0 ;
res_temperature_coefficient Simple Attribute
Specifies the first-order temperature coefficient for the resistance unit area of a routing
layer.
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Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
res_temperature_coefficient : value
float
;
...
}
}
}
}
value
A floating-point number that represents the coefficient value.
Example
res_temperature_coefficient : 0.0375 ;
resistance Simple Attribute
Specifies the aggregate resistance per contact cut.
Syntax
phys_library(library_name
id
) {
process_resource() {
process_wire_rule(wire_rule_name
id
) {
process_via(via_name
id
) {
resistance : value
float
;
...
}
}
}
}
value
A floating-point number representing the resistance value.
Example
resistance : 1.000e+00 ;
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Specifying Attributes and Groups in the macro
Group
For each cell, you use the macro group to specify the macro-level information and pin
information. Macro-level information includes such properties as symmetry, size and
obstruction. Pin information includes such properties as geometry and position.
This chapter describes the attributes and groups that you define in the macro group, with
the exception of the pin group, which is described in Chapter 9.
macro Group
Use this group to specify the physical aspects of the cell.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
...
}
}
cell_name
Specifies the name of the cell.
Note:
This name must be identical to the name of the logical cell_name
that you define in the library.
Example
macro(and2) {
...
}
Simple Attributes
cell_type
create_full_pin_geometry
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macro Group
eq_cell
extract_via_region_within_pin_area
in_site
in_tile
leq_cell
source
symmetry
Complex Attributes
extract_via_region_from_cont_layer
obs_clip_box
origin
size
Groups
foreign
obs
site_array
pin
cell_type Simple Attribute
Use this attribute to specify the cell type.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
cell_type : value
enum
;
...
}
}
}
value
See Table 2 for value definitions.
Example
cell_type : block ;
Table 2 cell_type Values
Cell type Definition
antennadiode_core Dissipates a manufacturing charge from a diode.
areaio_pad Area I/O driver
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macro Group
Cell type Definition
blackbox_block Subclass of block
block Predefined macro used in hierarchical design
bottomleft_endcap I/O cell placed at bottom-left corner
bottomright_endcap I/O cell placed at bottom-right corner
bump_cover Subclass of cover
core Core cell
cover A cover cell is fixed to the floorplan
feedthru_core Connects to another cell.
inout_pad Bidirectional pad cell
input_pad Input pad cell
output_pad Output pad cell
pad I/O cell
post_endcap Cell placed at the left or top end of core rows to connect
with the power ring
power_pad Power pad
pre_endcap Cell placed at the right or bottom end of core rows to
connect with the power ring
ring Blocks that can cut prerouted special nets and connect
to these nets with ring pins
spacer_core Fills space between regular core cells.
spacer_pad Spacer pad
tiehigh_core Connects I/O terminals to the power or ground.
tielow_core Connects I/O terminals to the power or ground.
topleft_endcap I/O cell placed at top-left corner
topright_endcap I/O cell placed at top-right corner
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macro Group
create_full_pin_geometry Simple Attribute
Use this attribute to specify the full pin geometry.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
create_full_pin_geometry : value
Boolean
;
...
}
}
value
Valid values are TRUE and FALSE.
Example
create_full_pin_geometry : TRUE ;
eq_cell Simple Attribute
Use this attribute to specify an electrically equivalent cell that has the same functionality,
pin positions, and electrical characteristics (such as timing and power) as a previously
defined cell.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
eq_cell : eq_cell_name
id
;
...
}
}
eq_cell_name
The name of the equivalent cell previously defined in the phys_library group.
Example
eq_cell : and2a ;
extract_via_region_within_pin_area Simple Attribute
Use this attribute to whether to extract via region information from within the pin area only.
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Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
extract_via_region_within_pin_area : value
Boolean
;
...
}
}
value
Valid values are TRUE and FALSE (default).
Example
extract_via_region_within_pin_area : TRUE ;
in_site Simple Attribute
Use this attribute to specify the site associated with a cell. The site class and symmetry
must match the cell class and symmetry.
Note:
You can use this attribute only with standard cell libraries.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
in_site : site_name
id
;
...
}
}
site_name
The name of the associated site.
Example
in_site : core ;
in_tile Simple Attribute
The in_tile attribute specifies the tile associated with a cell.
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Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
in_tile : tile_name
id
;
...
}
}
value
The name of the associated tile.
Example
in_tile : ;
leq_cell Simple Attribute
Use this attribute to specify a logically equivalent cell that has the same functionality and
pin interface as a previously defined cell. Logically equivalent cells need not have the
same electrical characteristics, such as timing and power.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
leq_cell : leq_cell_name
id
;
...
}
}
leq_cell_name
The name of the equivalent cell previously defined in the phys_library group.
Example
leq_cell : and2x2 ;
source Simple Attribute
Use this attribute to specify the source of a cell.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
source : value
enum
; ...
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}
}
value
Valid values are user (for a regular cell), generate (for a parametric cell), and
block (for a block cell).
Example
source : user ;
symmetry Simple Attribute
Use this attribute to specify the acceptable orientation for the macro. The cell symmetry
must match the associated site symmetry. When the attribute is not specified, a cell
is considered asymmetric. The allowable orientations of the cell are derived from the
symmetry.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
symmetry : value
enum
;
...
}
}
value
Valid values are r, x, y, xy, and rxy.
where
r
Specifies symmetry in 90 degree counterclockwise rotation
x
Specifies symmetry about the x-axis
y
Specifies symmetry about the y-axis
xy
Specifies symmetry about the x-axis and the y-axis
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rxy
Specifies symmetry about the x-axis and the y-axis and in 90 degree
counterclockwise rotation increments
Example
symmetry : r ;
extract_via_region_from_cont_layer Complex Attribute
Use this attribute to extract via region information from contact layers.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
extract_via_region_from_cont_layer(cont_layer_name
id
,
cont_layer_name
id
, ... ) ;
...
}
}
cont_layer_name
A list of one or more string values representing the contact layer names.
Example
extract_via_region_from_cont_layer () ;
obs_clip_box Complex Attribute
Use this attribute to specify a rectangular area of a cell layout in which connections are not
allowed or not desired. The resulting rectangle becomes an obstruction. Use this attribute
at the macro group level to customize the rectangle size for a cell. The values you specify
at the macro group level override the values you set in the pseudo_phys_library group.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs_clip_box( top
float
, right
float
,
bottom
float
, left
float
) ;
...
}
}
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top, right, bottom, left
Floating-point numbers that specify the coordinates for the corners of the
rectangular area.
Example
obs_clip_box(165000, 160000, 160000, 160000) ;
origin Complex Attribute
Use this attribute to specify the origin of a cell, which is the lower-left corner of the
bounding box.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
origin(num_x
float
, num_y
float
) ;
...
}
}
num_x, num_y
Floating-point numbers that specify the origin coordinates.
Example
origin(0.0, 0.0) ;
size Complex Attribute
Use this attribute to specify the size of a cell. This is the minimum bounding rectangle for
the cell. Set this to a multiple of the placement grid.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
size(num_x
float
, num_y
float
) ;
...
}
}
}
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num_x, num_y
Floating-point numbers that represent the cell bounding box dimension. For
standard cells, the height should be equal to the associated site height and the
width should be a multiple of the site width.
Example
size(0.9, 7.2) ;
foreign Group
Use this group to specify the associated GDSII structure (model) of a macro. Used for
GDSII input and output to adjust the coordinate and orientation variations between GDSII
and the physical library.
Note:
Only one foreign group is allowed in a macro group.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
foreign(foreign_object_name
id
) {
...
}
}
}
foreign_object_name
The name of the corresponding GDSII cell (model).
Example
foreign(and12a) {
...
}
Simple Attribute
orientation
Complex Attribute
origin
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orientation Simple Attribute
Use this attribute to specify the orientation of the GDSII foreign cell.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
foreign(foreign_object_name
string
) {
orientation : value
enum
;
...
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 5.
Figure 5 Orientation Examples
Example
orientation : N ;
origin Complex Attribute
Use this attribute to specify the equivalent coordinates of a placed macro origin in the
GDSII coordinate system.
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Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
foreign(foreign_object_name
id
) {
origin(x
float
, y
float
) ;
...
}
}
}
x, y
Floating-point numbers that specify the GDSII coordinates where the macro
origin is placed.
Example
The example shows that the macro origin (the lower-left corner) is located at (-2.0, -3.0) in
the GDSII coordinate system.
origin(-2.0, -3.0) ;
obs Group
Use this group to specify an obstruction on a cell.
Note:
The obs group does not take a name.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
...
}
}
}
Example
obs() {
...
}
Complex Attributes
via
via_iterate
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geometry
via Complex Attribute
Use this attribute to specify a via instance at the given coordinates.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
via(via_name
id
, x
float
, y
float
);
...
}
}
}
via_name
The name of a via already defined in the resource group.
x, y
Floating-point numbers that represent the x- and y-coordinates for placement.
Example
via(via12, 0, 100) ;
via_iterate Complex Attribute
Use this attribute to specify an array of via instances in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
via_iterate(num_x
int
, num_y
int
, space_x
float
,
space_y
float
, via_name
id
, x
float
, y
float
) ;
...
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
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space_x, space_y
Floating-point numbers that specify the value for spacing between each via
origin.
via_name
Specifies the name of a previously defined via to be instantiated.
x, y
Floating-point numbers that specify the endpoints.
Example
via_iterate(2, 2, 2.000, 3.000.0, via12, 176.0, 1417.0) ;
geometry Group
Use this group to specify the geometries of an obstruction on the specified macro.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
...
}
}
}
}
layer_name
Specifies the name of the layer where the obstruction is located.
Example
geometry(metal) {
...
}
Simple Attributes
core_blockage_margin
feedthru_area_layer
generate_core_blockage
preserve_current_layer_blockage
treat_current_layer_as_thin_wire
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Complex Attributes
max_dist_to_combine_current_layer_blockage
path
path_iterate
polygon
polygon_iterate
rectangle
rectangle_iterate
core_blockage_margin Simple Attribute
Use this attribute to specify a value for computing the margin of a block core.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
core_blockage_margin : value
float
;
...
}
}
}
}
value
A positive floating-point number representing the margin.
Example
core_blockage_margin : 0.0 ;
feedthru_area_layer Simple Attribute
Use this attribute to prevent an area from being covered with a blockage and to prevent
any merging from occuring within the specified area on the corresponding layer.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
feedthru_area_layer : value
id
;
...
}
}
}
}
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value
A string representing the layer name.
Example
core_blockage_margin : 0.0 ;
generate_core_blockage Simple Attribute
Use this attribute to specify whether to generate the core blockage information.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
generate_core_blockage : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE (default).
Example
generate_core_blockage : TRUE ;
preserve_current_layer_blockage Simple Attribute
Use this attribute to specify whether to preserve the current layer blockage information.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
preserve_current_layer_blockage : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE (default).
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Example
preserve_current_layer_blockage : TRUE ;
treat_current_layer_as_thin_wires Simple Attribute
Use this attribute to specify whether to treat the current layer as thin wires.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
treat_current_layer_as_thin_wires : value
Boolean
;
...
}
}
}
}
value
Valid values are TRUE and FALSE (default).
Example
treat_current_layer_as_thin_wires : TRUE ;
max_dist_to_combine_current_layer_blockage Complex Attribute
Use this attribute to specify a maximum distance value, beyond which blockages on the
current layer are not combined.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
max_dist_to_combine_current_layer_blockage
( value
float
, value
float
) ;
...
}
}
}
}
value
Floating-point numbers that represent the maximum distance value.
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Example
max_dist_to_combine_current_layer_blockage ( ) ;
path Complex Attribute
Use this attribute to specify a shape by connecting specified points. The drawn geometry
is extended on both endpoints by half the wire width.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
path(width
float
, x1
float
, y1
float
, ..., ...,
xn
float
, yn
float
) ;
...
}
}
}
}
width
Floating-point number that represents the width of the path shape.
x1,y1,..., ...., xn,yn
Floating-point numbers that represent the x- and y-coordinates for each point
that defines a trace. The path shape is extended from the trace outward by one
half the width on both sides. If only one point is specified, a square centered on
that point is generated. The width of the generated square equals the width
value.
Example
path(2.0,1,1,1,4,10,4,10,8) ;
path_iterate Complex Attribute
Represents an array of paths in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
path_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
width
float
, x1
float
, y1
float
,...,
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xn
float
, yn
float
)
...
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Specify the value for spacing around the path.
width
Floating-point number that represents the width of the path shape.
x1, y1
Floating-point numbers that represent the first path point.
xn, yn
Floating-point numbers that represent the final path point.
Example
path_iterate(2,1,5.000,5.000,2.0,1,1,1,4,10,4,10,8) ;
polygon Complex Attribute
Represents a rectilinear polygon by connecting all the specified points.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
polygon(x1, y1, ..., xn, yn) ;
...
}
}
}
}
x1,y1,...,xn,yn
Floating-point numbers that represent the x- and y-coordinates for each point
that defines the shape. Specify a minimum of four points.
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You are responsible for ensuring that the resulting polygon is orthogonal.
Example
polygon(175.500, 1414.360, 176.500, 1414.360, 176.500,
1417.360, 175.500, 1417.360) ;
polygon_iterate Complex Attribute
Represents an array of rectilinear polygons in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
polygon_iterate (num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
x1
float
, y1
float
, x2
float
,
y2
float
, x3
float
, y3
float
,...,
xn
float
, yn
float
) ;
...
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around the polygon.
x1, y1; x2, y2; x3, y3; ..., ...; xn, yn
Floating-point numbers that represent successive points of the polygon.
Note:
You must specify at least four points.
Example
polygon_iterate(2, 2, 2.000, 4.000, 175.500, 1414.360,
176.500, 1414.360, 176.500, 1417.360,
175.500, 1417.360) ;
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rectangle Complex Attribute
Represents a rectangle.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
rectangle(x1
float
, y1
float
, x2
float
, y2
float
) ;
...
}
}
}
}
x1, y1, x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangle.
Example
rectangle(2, 0, 4, 0) ;
rectangle_iterate Complex Attribute
Represents an array of rectangles in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
obs() {
geometry(layer_name
id
) {
rectangle_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
x1
float
, y1
float
, x2
float
, y2
float
)
...
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around the rectangles.
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x1, y1; x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangles.
Example
rectangle_iterate(2, 2, 2.000, 4.000, 175.500, 1417.360,
176.500, 1419.140) ;
site_array Group
Use this group to specify the site array associated with a cell. The site class and site
symmetry must match the cell class and cell symmetry.
Note:
You can use this attribute only with gate array libraries.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
site_array(site_name
id
) {
...
}
}
}
site_name
The name of a site already defined in the resource group.
Example
site_array(core) {
...
}
Simple Attribute
orientation
Complex Attributes
iterate
origin
orientation Simple Attribute
Use this attribute to specify how you place the cells in an array.
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Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
site_array (site_name
id
) {
orientation : value
enum
;
...
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 6.
Figure 6 Orientation Examples
Example
orientation : N ;
iterate Complex Attribute
Use this attribute to specify the dimensions and arrangement of an array of sites.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
site_array(site_name
id
) {
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iterate(num_x
int
, num_y
int
, space_x
int
,
space_y
int
) ;
...
}
}
}
num_x, num_y
Integer numbers that represent the number of rows and columns in an array,
respectively.
space_x, space_y
Floating-point numbers that represent the row and column spacing, respectively.
Example
iterate(17, 1, 0.98, 11.76) ;
origin Complex Attribute
Use this attribute to specify the origin of a site array.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
site_array (site_name
id
) {
origin(x
float
, y
float
) ;
...
}
}
}
x, y
Floating-point numbers that specify the origin coordinates of the site array.
Example
origin(0.0, 0.0) ;
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Specifying Attributes and Groups in the pin
Group
For each cell, you use the macro group to specify the macro-level information and pin
information. Macro-level information includes such properties as symmetry, size and
obstruction. Pin information includes such properties as geometry and position.
This chapter describes the attributes and groups that you define in the pin group within
the macro group.syntaxpin group
pin Group
Use this group to specify one pin in a cell group.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
}
}
}
pin_name
Specifies the name of the pin. This name must be identical to the name of the
logical pin_name that you define in the library.
Example
pin(A) {
...
pin description
...
}
Simple Attributes
capacitance
direction
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eq_pin
must_join
pin_shape
pin_type
Complex Attributes
antenna_contact_accum_area
antenna_contact_accum_side_area
antenna_contact_area
antenna_contact_area_partial_ratio
antenna_contact_side_area
antenna_contact_side_area_partial_ratio
antenna_diffusion_area
antenna_gate_area
antenna_metal_accum_area
antenna_metal_accum_side_area
antenna_metal_accum_side_area_partial_ratio
antenna_metal_area
antenna_metal_area_partial_ratio
Groups
foreign
port
capacitance Simple Attribute
Use this attribute to specify the capacitance value for a pin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
capacitance : value
float
;
...
}
}
}
value
A floating-point number representing the capacitance value.
Example
capacitance : 1.0 ;
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direction Simple Attribute
Use this attribute to specify the direction of a pin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
direction : value
enum
;
...
}
}
}
value
Valid values are inout, input, feedthru, output, and tristate.
Example
direction : inout ;
eq_pin Simple Attribute
Use this attribute to specify an electrically equivalent pin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
eq_pin : pin_name
id
;
...
}
}
}
pin_name
The name of an electrically equivalent pin.
Example
eq_pin : A ;
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must_join Simple Attribute
Use this attribute to specify the name of a pin that must be connected to the pin_group
pin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
must_join : pin_name
id
;
...
}
}
}
pin_name
The name of the pin that must be connected to the pin_group pin.
Example
must_join : A ;
pin_shape Simple Attribute
Use this attribute to specify the pin shape.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
pin_shape : value
enum
;
...
}
}
}
value
Valid values are ring, abutment, and feedthru.
Example
pin_shape : ring ;
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pin_type Simple Attribute
Use this attribute to specify what a pin is used for.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
pin_type : value
enum
;
...
}
}
}
value
Valid values are clock, power, signal, analog, and ground.
Example
pin_type : clock ;
antenna_contact_accum_area Complex Attribute
Use this attribute to specify the cumulative contact area.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_accum_area (value
float
);
...
}
}
}
value
A floating-point number that represents the antenna.
Example
antenna_contact_accum_area ( 0.0 ) ;
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antenna_contact_accum_side_area Complex Attribute
Use this attribute to specify the cumulative side area.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_accum_side_area (value
float
);
...
}
}
}
value
A floating-point number that represents the antenna.
Example
antenna_contact_accum_side_area ( 0.0 ) ;
antenna_contact_area Complex Attribute
Use this pin-specific attribute and the following attributes to specify contributions
coming from intracell geometries: antenna_contact_area, antenna_contact_length,
total_antenna_contact_length. These attributes together account for all the
geometries, including the ports of pins that appear in the cell’s physical model.
For black box cells, use this pin-specific attribute along with antenna_contact_length
and antenna_contact_perimeter to specify the amount of metal connected to a block
pin on a given layer.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_area (value
float
);
...
}
}
}
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value
A floating-point number that represents the contributions coming from intracell
geometries.
Example
antenna_contact_area (0.3648, 0,0,0,0,0) ;
antenna_contact_area_partial_ratio Complex Attribute
Use this attribute to specify the antenna ratio of a contact.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_area_partial_ratio (value
float
);
...
}
}
}
value
A floating-point number that represents the ratio.
Example
antenna_contact_area_partial_ratio ( 0.0 ) ;
antenna_contact_side_area Complex Attribute
Use this attribute to specify the side wall area of a contact.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_side_area (value
float
);
...
}
}
}
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value
A floating-point number that represents the ratio.
Example
antenna_contact_side_area ( 0.0 ) ;
antenna_contact_side_area_partial_ratio Complex Attribute
Use this attribute to specify the antenna ratio using the side wall area of a contact.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_contact_side_area_partial_ratio
(value
float
);
...
}
}
}
value
A floating-point number that represents the ratio.
Example
antenna_contact_side_area_partial_ratio ( 0.0 ) ;
antenna_diffusion_area Complex Attribute
For black box cells, use this attribute to specify the total diffusion area connected to a
block’s pin using layers less than or equal to the pin’s layer.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_diffusion_area (value
float
,value
float
value
float
...) ;
...
}
}
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}
value
Floating-point numbers representing the total diffusion area.
Example
antenna_diffusion_area (0.0, 0.0, 0.0, ...);
antenna_gate_area Complex Attribute
For black box cells, use this attribute to specify the total gate area connected to a block’s
pin using layers less than or equal to the pin’s layer.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_gate_area (value
float
,value
float
value
float
...) ;
...
}
}
}
value, value, value, ...
Floating-point numbers that represent the total gate area.
Example
antenna_gate_area (0.0, 0.0, 0.0, ...) ;
antenna_metal_accum_area Complex Attribute
Use this attribute to specify the cumulative metal area.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_accum_area (value
float
);
...
}
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}
}
value
A floating-point number that represents the antenna.
Example
antenna_metal_accum_area () ;
antenna_metal_accum_side_area Complex Attribute
Use this attribute to specify the cumulative side area.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_accum_side_area (value
float
);
...
}
}
}
value
A floating-point number that represents the antenna.
Example
antenna_metal_accum_side_area () ;
antenna_metal_area Complex Attribute
Use this pin-specific attribute and antenna_metal_area to specify contributions coming
from intracell geometries. These attributes together account for all the geometries,
including the ports of pins that appear in the cell’s physical model.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_area (value
float
);
...
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}
}
}
value
A floating-point number that represents the contributions coming from intracell
geometries.
Example
antenna_metal_area (0.3648, 0,0,0,0,0) ;
antenna_metal_area_partial_ratio Complex Attribute
Use this attribute to specify the antenna ratio of a metal wire.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_area_partial_ratio (value
float
);
...
}
}
}
value
A floating-point number that represents the ratio.
Example
antenna_metal_area_partial_ratio () ;
antenna_metal_side_area Complex Attribute
Use this attribute to specify the side wall area of a metal wire.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_side_area (value
float
);
...
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}
}
}
value
A floating-point number that represents the ratio.
Example
antenna_metal_side_area () ;
antenna_metal_side_area_partial_ratio Complex Attribute
Use this attribute to specify the antenna ratio using the side wall area of a metal wire.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
antenna_metal_side_area_partial_ratio (value
float
);
...
}
}
}
value
A floating-point number that represents the ratio.
Example
antenna_metal_side_area_partial_ratio () ;
foreign Group
Use this group to specify which GDSII structure (model) to use when an instance of a pin
is placed. Only one foreign group is allowed in a library.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
foreign(foreign_object_name
id
) {
...
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}
}
}
}
foreign_object_name
The name of the GDSII structure (model).
Example
foreign(via34) {
...
}
Simple Attribute
orientation
Complex Attribute
origin
orientation Simple Attribute
Use this attribute to specify how you place the cells in an array in relation to the VDD and
VSS buses.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
foreign(foreign_object_name
id
) {
orientation : value
enum
;
...
}
}
}
}
value
Valid values are N (north), E (east), S (south), W (west), FN (flip north), FE (flip
east), FS (flip south), and FW (flip west), as shown in Figure 7.
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Figure 7 Orientation Examples
Example
orientation : N ;
origin Complex Attribute
Use this attribute to specify the equivalent coordinates of a placed foreign origin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
...
foreign(foreign_object_name
id
) {
...
origin(x
float
, y
float
) ;
}
}
}
}
x,y
Floating-point numbers that specify the coordinates of the foreign object’s origin.
Example
origin(-1, -1) ;
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port Group
Use this group to specify the port geometries for a pin.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
...
}
}
}
}
Note:
The port group does not take a name.
Example
port() {
...
}
Complex Attributes
via
via_iterate
Group
geometry
via Complex Attribute
Use this attribute to instantiate a via relative to the origin implied by the coordinates
(typically the center).
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
via(via_name
id
, x, y) ;
...
}
}
}
}
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via_name
A previously defined via.
x
The horizontal coordinate.
y
The vertical coordinate.
Example
via(via23, 25.00, -30.00) ;
via_iterate Complex Attribute
Use this attribute to instantiate an array of vias in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
...
via_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
via_name
id
, x
float
, y
float
) ;
...
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around each via.
via_name
Specifies the name of a previously defined via.
x, y
Floating-point numbers that specify the location of the first via.
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Example
via_iterate(2, 2, 100, 100, via12, 0, 0) ;
geometry Group
Use this group to specify the geometry of an obstruction or a port.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
...
geometry(layer_name
id
) {
}
}
}
}
layer_name
The layer where the shape is defined.
Example
geometry(cut01) {
...
}
Complex Attributes
path
path_iterate
polygon
polygon_iterate
rectangle
rectangle_iterate
path Complex Attribute
Use this attribute to specify a shape by connecting specified points. The drawn geometry
is extended by half the default wire width of the layer on both endpoints.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
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path(width
float
, x1
float
, y1
float
, ..., ...,
xn
float
, yn
float
)
...
}
}
}
}
}
width
Floating-point number that represents the width of the path shape.
x1,y1; ..., ....; xn,yn
Floating-point numbers that represent the x- and y-coordinates for each point
that defines a trace. The path shape is extended from the trace by one half of
the width on both sides. If only one point is specified, a square centered on that
point is generated. The width of the generated square equals the width value.
Example
path(1,1,4,4,10,10,5,10) ;
path_iterate Complex Attribute
Use this attribute to specify an array of paths in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
...
path_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
width
float
, x1
float
, y1
float
,...,
xn
float
, yn
float
)
...
}
}
}
}
}
num_x, num_y
Integer numbers that, respectively, represent the number of columns and rows in
the array.
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space_x, space_y
Floating-point numbers that specify the value for spacing around the path.
width
Floating-point number that represents the width of the path shape.
x1, y1
Floating-point numbers that represent the first path point.
xn, yn
Floating-point numbers that represent the final path point.
Example
path_iterate(2, 1, 5.000, 5.000, 1.000, 174.500, 1419.140,
177.500, 1422.140) ;
polygon Complex Attribute
Use this attribute to specify a rectilinear polygon by connecting all the specified points.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
...
polygon(x1
float
, y1
float
; ..., ...,
xn
float
, yn
float
)
...
}
}
}
}
}
x1,y1; ..., ....; xn,yn
Floating-point numbers that represent the x- and y-coordinates for each point
that defines the shape. You should specify a minimum of four points.
Note:
You are responsible for ensuring that the resulting polygon is
rectilinear.
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Example
polygon(175.500, 1414.360, 176.500, 1414.360, 176.500,
1417.360, 175.500, 1417.360) ;
polygon_iterate Complex Attribute
Use this attribute to specify an array of polygons in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
...
polygon_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
x1
float
, y1
float
, x2
float
,
y2
float
, x3
float
, y3
float
,...,
xn
float
, yn
float
)
...
}
}
}
}
}
num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around the polygon.
x1, y1; x2, y2; x3, y3; ..., ...; xn, yn
Floating-point numbers that represent successive points of the polygon.
Note:
You must specify at least four points.
Example
polygon_iterate(2, 2, 2.000, 4.000, 175.500, 1414.360,
176.500, 1414.360, 176.500, 1417.360,
175.500, 1417.360) ;
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rectangle Complex Attribute
Use this attribute to specify a rectangular shape.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
...
rectangle(x1
float
, y1
float
, x2
float
, y2
float
)
...
}
}
}
}
}
x1, y1, x2, y2
Floating-point number that specify the coordinates for the diagonally opposing
corners of the rectangle.
Example
rectangle(2, 0, 4, 0) ;
rectangle_iterate Complex Attribute
Use this attribute to specify an array of rectangles in a particular pattern.
Syntax
phys_library(library_name
id
) {
macro(cell_name
id
) {
pin(pin_name
id
) {
port() {
geometry(layer_name
id
) {
...
rectangle_iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
,
x1
float
, y1
float
, x2
float
, y2
float
)
...
}
}
}
}
}
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num_x, num_y
Integer numbers that represent the number of columns and rows in the array,
respectively.
space_x, space_y
Floating-point numbers that specify the value for spacing around the rectangles.
x1, y1; x2, y2
Floating-point numbers that specify the coordinates for the diagonally opposite
corners of the rectangles.
Example
rectangle_iterate(2, 2, 2.000, 4.000, 175.5, 1417.360,
176.500, 1419.140) ;
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Developing a Physical Library
The physical library specifies the information required for floor planning, RC estimation
and extraction, placement, and routing.
You use the physical library syntax (.plib) to model your physical library.
This chapter includes the following sections:
•
Creating the Physical Library
•
Naming the Source File
• Naming the Physical Library
•
Defining the Units of Measure
Creating the Physical Library
This section describes how to name your source file and library, and how to define the
units of measure for properties in your library.
Naming the Source File
The recommended file name suffix for physical library source files is .plib.
Example
myLib.plib
Naming the Physical Library
You specify the name for your physical library in the phys_library group, which is always
the first executable line in a library source file.
Syntax
phys_library(library_name
id
) {
...
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}
Use the comment, date, and revision attributes to document your library source file.
Example
phys_library(sample) {
comment : "my library" ;
date : "1st Jan 2002" ;
revision : "Revision 2.0.5" ;
}
Defining the Units of Measure
Use the phys_library group attributes described in Table 3 to specify the units of
measure for properties such as capacitance and resistance. The unit statements must
precede other definitions, such as the technology data, design rules, and macros.
Syntax
phys_library (library_name
id
) {
...
attribute_name : value
enum
;
...
}
Example
phys_library(sample) {
capacitance_unit : 1pf ;
distance_unit : 1um ;
resistance_unit : 1ohm ;
...
}
Table 3 lists the attribute names and values that you can use to define the units of
measure.
Table 3 Units of Measure
Property Attribute name Legal values
Capacitance capacitance_unit 1pf, 1ff, 10ff, 100ff
Distance distance_unit 1um, 1mm
Resistance resistance_unit 1ohm, 100ohm, 10ohm, 1kohm
Time time_unit 1ns, 100ps, 10ps, 1ps
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Property Attribute name Legal values
Voltage voltage_unit 1mV, 10mV, 100mV, 1V
Current current_unit 100uA, 100mA, 1A, 1uA, 10uA, 1mA,
10mA
Power power_unit 1mw
Database
distance
resolution
dist_conversion_factor Any multiple of 100
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Defining the Process and Design Parameters
The physical library specifies the information required for floor planning, RC estimation
and extraction, placement, and routing.
You use the physical library syntax (.plib) to model your physical library.
This chapter includes the following sections:
•
Defining the Technology Data
•
Defining the Architecture
• Defining the Layers
•
Defining Vias
•
Defining the Placement Sites
Defining the Technology Data
Technology data includes the process and electrical design parameters. Site-array and
cell data refer to the technology data; therefore, you must define the layer data before you
define site-array and cell data.
Defining the Architecture
You specify the architecture and the layer information in the resource group inside the
phys_library group.
Syntax
phys_library(library_name
id
) {
resource(architecture
enum
) {
...
}
}
architecture
The valid values are std_cell and array.
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Defining the Technology Data
Example
phys_library(mylib) {
...
resource(std_cell) {
...
}
}
Defining the Layers
The layer definition is order dependent. You define the layers starting with the layer closest
to the substrate and ending with the layer furthest from the substrate.
Depending on their purpose, the layers can include
•
Contact layer
•
Overlap layer
• Routing layer
•
Device layer
Contact Layer
Contact layers define the contact cuts that enable current to flow between the device and
the first routing layer or between any two routing layers; for example, cut01 between poly
and metal1, or cut12 between metal1 and metal2. You define the contact layer by using
the contact_layer attribute inside the resource group.
Syntax
resource(architecture
enum
) {
contact_layer(layer_name
id
)
...
}
Example
contact_layer(cut01) ;
Overlap Layer
An overlap layer provides accurate overlap checking of rectilinear blocks. You define the
overlap layer by using the overlap_layer attribute inside the resource group.
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Defining the Technology Data
Syntax
resource(architecture
enum
) {
overlap_layer(layer_name
id
)
...
}
Example
resource(std_cell) {
overlap_layer(mod) ;
...
}
Routing Layer
You define the routing layer and its properties by using the routing_layer group inside
the resource group.
Syntax
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
attribute : value
float
;
...
}
}routing layersyntaxrouting layerattributeslayersrouting
Example
resource(std_cell) ; {
routing_layer(m1) { /* metal1 layer definition */
cap_per_sq : 3.200e-04 ;
default_routing_width : 3.200e-01 ;
res_per_sq : 7.000e-02 ;
routing_direction : horizontal ;
pitch : 9.000e-01;
spacing : 3.200e-01 ;
cap_multiplier : ;
shrinkage : ;
thickness : ;
}
}
Table 4 lists the attributes you can use to specify routing layer properties.
Note:
All numerical values are floating-point numbers.
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Table 4 Routing Layer Simple Attributes
Attribute name Valid values Property
default_routing_width > 0.0 Minimum metal width allowed on the layer;
the default width for regular wiring
cap_per_sq > 0.0 Capacitance per square unit between
a layer and a substrate, used to model
wire-to-ground capacitance
res_per_sq > 0.0 Resistance per square unit
coupling_cap > 0.0 Coupling capacitance between parallel wires
on the same layer
fringe_cap > 0.0 Fringe (sidewall) capacitance per unit length
of a routing layer
routing_direction horizontal,
vertical
Preferred routing direction
pitch > 0.0 Routing pitch
spacing > 0.0 Default different net spacing (edge-edge) for
regular wiring on a layer
cap_multiplier > 0.0 Cap multiplier; accounts for changes in
capacitance due to nearby wires
shrinkage > 0.0 Shrinkage of metal EffWidth = MetalWidth –
Shrinkage
thickness > 0.0 Thickness
height >0.0 The distance from the top of the substrate to
the bottom of the routing layer
offset > 0.0 The offset from the placement grid to the
routing grid
edgecapacitance > 0.0 Total peripheral capacitance per unit length
of a wire on the routing layer
inductance_per_dist > 0.0 Inductance per unit length of a routing layer
antenna_area_factor > 0.0 Antenna effect; to limit the area of wire
segments
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Specifying Net Spacing
Use the ranged_spacing complex attribute to specify the different net spacing for special
wiring on the layer. You can also use this attribute to specify the minimum spacing for a
particular routing width range of the metal. You can use more than one ranged_spacing
attribute to specify spacing rules for different ranges.
Each ranged_spacing attribute requires floating-point values for the minimum width for
the wiring range, the maximum width for the wiring range, and the minimum spacing for
the net.
Syntax
resource(architecture
enum
) {
routing_layer(layer_name
id
) {
...
ranged_spacing(value
float
, value
float
, value
float
) ;
...
}
}
Example
routing_layer(m1) {
...
ranged_spacing(1.60, 2.40, 1.20) ;
...
}
Device Layer
Device layers make up the transistors below the routing layers—for example, the poly
layer and the active layer. To define the device layer, use the device_layer attribute
inside the resource group.
Wires are not allowed on device layers. If pins appear in the device layer, you must define
vias to permit the router to connect the pins to the first routing layer.
Syntax
resource(architecture
enum
) {
device_layer(layer_name
id
) ;
...
}
Example
resource(std_cell) {
device_layer (poly) ;
...
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}
Defining Vias
A via is the routing connection for wires in each pair of connected layers. Vias typically
comprise three layers: the two connected layers and the cut layer between the connected
layers.
Naming the Via
You define the via name in the via group inside the resource group.
Syntax
resource(architecture
enum
) {
via(via_name
id
) {
...
}
}
Example
resource(std_cell) {
...
via(via23) {
...
}
...
}
Defining the Via Properties
You define the via properties by using the following attributes inside the via group.
•
is_default
•
top_of_stack_only
• resistance
Syntax
via(via_name
id
) {
is_default : Boolean ;
top_of_the_stack : Boolean ;
resistance : float ;
...
}
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Example
via(via23) {
is_default : TRUE;
top_of_stack_only : FALSE;
resistance : 1.0;
...
}
Table 5 lists the properties you can define with the via attributes.
Table 5 Defining Via Properties
Attribute name Valid values Property
is_default TRUE, FALSE Default via for a given layer pair
top_of_stack_only TRUE, FALSE Use only on top of a via stack
resistance floating-point
number
Resistance per contact-cut rectangle
Defining the Geometry for Simple Vias
Define the via geometry (or geometries) by using via_layer groups inside a via group.
Each via_layer group defines the via geometry for one layer. Use the name of the layer
as the via_layer group name.
The layer1 and layer2 layers are the adjacent routing layers, where layer1 is closer to the
substrate. The contact layer is the cut layer between layer1 and layer2.
For rectilinear vias, you define the geometry by using more than one rectangle function for
the corresponding layer.
Syntax
via_layer(layer1_name
id
) {
rectangle(x11
float
, y11
float
, x21
float
, y21
float
) ;
/* 1 or more rectangles */
}
via_layer(contact_name
id
) {
rectangle(x1c
float
, y1c
float
, x2c
float
, y2c
float
) ;
/* 1 or more rectangles */
}
via_layer(layer2_name
id
) {
rectangle(x12
float
, y12
float
, x22
float
, y22
float
) ;
/* 1 or more rectangles */
}
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where (x11, y11), (x21, y21), (x1c, y1c), (x2c, y2c), (x21, y12), and (x22, y22) are the
coordinates of the opposite corners of the rectangle.
Example
via(via 45) {
is_default : TRUE ;
resistance : 1.5 ;
via_layer(metal4) {
rectangle(-0.3, -0.3, 0.3, 0.3) ;
}
via_layer(cut45) {
rectangle(-0.18, -0.18, 0.18, 0.18) ;
}
via_layer(meta15) {
rectangle(-0.27, -0.27, 0.27, 0.27) ;
}
}
Defining the Geometry for Special Vias
Special vias are vias that have
•
Fewer than three layers, with one layer being a contact layer
•
More than three layers
Vias With Fewer Than Three Layers
To define vias that have fewer than three layers, use the via_layer group, as shown
below.
Syntax
via_layer(via_name
id
) {
rectangle(x1
float
, y1
float
, x2
float
, y2
float
) ; }
where (x1, y1) and (x2, y2) are the coordinates (floating-point numbers) for the opposite
corners of the rectangle, as shown in Figure 8.
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Figure 8 Coordinates of a Rectangle
Example
via_layer(cut23) {
rectangle(-0.18, -0.18, 0.18, 0.18) ;
}
Vias With More Than Three Layers
For vias with more than three layers, use multiple via_layer groups. You can have more
than one via_layer group in your physical library.
Syntax
via_layer (via_name
id
) {
rectangle(x1
float
, y1
float
, x2
float
, y2
float
) ; }
where (x1, y1) and (x2, y2) are the coordinates (floating-point numbers) for the opposite
corners of the rectangle.
Example
via(via123) {
resistance : 1.5 ;
via_layer(met1) {
rectangle(-0.3. -0.3, 0.3, 0.3):
}
via_layer(cut12) {
rectangle(-0.2. -0.2, 0.2, 0.2):
}
via_layer(met2) {
rectangle(-0.3. -0.3, 0.3, 0.3):
}
via_layer(met23) {
rectangle(-0.2. -0.2, 0.2, 0.2):
}
via_layer (met3) {
rectangle(-0.3, -0.3, 0.3, 0.3) ;
}
}
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Referencing a Foreign Structure
Use the foreign group to specify which GDSII structure (model) to use when you place
an instance of the via. You also use this group to specify the orientation and the offset with
respect to the GDSII structure origin.
Note:
Only one foreign reference is allowed for each via.
Syntax
foreign(foreign_structure_name
id
) {
orientation : N | E | W | S | FN | FE | FW | FS ;
origin(x
float
, y
float
) ;
}
where x and y represent the offset distance.
Example
via(via34) {
is_default : TRUE ;
resistance : 2.0e-02 ;
foreign(via34) {
orientation : FN ;
origin(-1, -1) ;
}
...
}
Defining the Placement Sites
For each class of cells (such as cores and pads), you must define the available sites for
placement. The methodology you use for defining placement sites depends on whether
you are working with standard cell technology or gate array technology.
Standard Cell Technology
For standard cell technologies you define the placement sites by defining the site name in
the site group inside the resource group, and by defining the site properties using the
following attributes inside the site group:
•
The site_class attribute specifies the site class. Two types of placement sites are
supported:
◦
Core (core cell placement)
◦
Pad (I/O placement)
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• The symmetry attribute specifies the site symmetry with respect to the x- and y-axes.
Note:
If you do not specify the symmetry attribute, the site is considered
asymmetric.
• The size attribute specifies the site size.
Syntax
resource(architecture
enum
) {
site(site_name
id
) {
site_class : core | pad ;
symmetry : x | y | r | xy | rxy ;
size(x_size
float
, y_size
float
) ;
}
}
site_name
The name of the library site. Common practice is to describe the function of the
site (core or pad) with the site name.
You can assign one of the following values to the symmetry attribute:
x
Specifies symmetry about the x-axis
y
Specifies symmetry about the y-axis
r
Specifies symmetry in 90 degree counterclockwise rotation
xy
Specifies symmetry about the x-axis and the y-axis
rxy
Specifies symmetry about the x-axis and the y-axis and in 90 degree
counterclockwise rotation increments
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Figure 9 Examples of X, Y, and R Symmetry
Figure 9 shows the relationship of the symmetry values to the axis.
Gate Array Technology
Follow these guidelines when working with gate array technologies:
•
Define the basic sites for the core and pad in the same way you would for standard cell
technologies.
•
Use the array group to define arrays for the site, the floorplan, and the detail routing
grid descriptions. You define the array group inside the resource group.
Defining the Floorplan Set
A floorplan is an array of sites that allow or disallow the placement of cells. You define a
floorplan group or multiple floorplan groups inside an array group.
A floorplan without a name becomes the default floorplan. Subsequently, when no
floorplan is specified, the default floorplan is used. Figure 10 shows the elements of a
floorplan on a die.
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Figure 10 Elements of a Floorplan
Instantiating the Site Array
You instantiate arrays by using the site_array group inside the floorplan group. The
orientation, availability for placement, origin, and the array pattern (that is, the number of
rows and columns, as well as the row spacing and column spacing) are all defined in the
site_array group.
Syntax
site(site_name
id
) {
stateless : pad | core;
symmetry : x | y | r | xy | rxy ;
size(x_size
float
, y_size
float
) ;
}
array(array_name
id
) {
...
floorplan(floorplan_name
id
) {
site_array(site_name
id
) {
orientation : N | E | W | S | FN | FE | FW | FS ;
placement_rule : regular | can_place |
cannot_place ;
origin(x
float
, y
float
) ;
iterate(num_x
int
, num_y
int
,
space_x
float
, space_y
float
) ;
}
}
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}
Table 6 shows the values and description for each of the attributes you use to define
placement sites.
Table 6 Placement Site Definitions
Attribute Valid values Description
site_class pad I/O cell placement site
core Core cell placement site
symmetry x, y, r, xy, rxy Symmetry
width, height Site dimensions
orientation N, E, W, S, FN, FE,
FW, FS
Orientation
placement_rule can_place Site array available for floorplan
cannot_place Site array not available for floorplan
regular Placement grid
origin x, y Coordinate of the origin of site array
iterate num_x Number of columns in the site array
num_y Number of rows in the site array
space_x Column spacing (float)
space_y Row spacing (float)
Example
site(core) {
site_class : core ;
symmetry : x ;
size (1, 10) ;
}
array(samplearray) {
...
floorplan() { /* default floorplan */
site_array(core) { /* Core cells placement */
orientation : N ;
placement_rule : can_place; /* available for placement */
origin(0, 0) ;
iterate(2, 4, 1.5, 0) ; /* site_array has 2 sites in x */
/*direction spaced 1.5 um apart, 4 */
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/*sites in y direction, spaced */
/*1.5 um apart */
}
}
}
Defining the Global Cell Grid
You define the global cell grid overlaying the array by using the routing_grid attribute
inside the array group. The router uses this grid during global routing.
Syntax
array(array_name
id
) {
routing_grid() {
routing_direction : horizontal | vertical ;
grid_pattern (start
float
, grids
integer
, spacing
float
) ;
}
where
start
A floating-point number representing the starting-point coordinate
grids
An integer number representing the number of grids in the x and y directions
spacing
A floating-point number representing the spacing between the grids in the x and
y directions
Example
array(samplearray) {
routing_grid(0, 3, 1, 0, 3, 1) ;
routing_direction(horizontal) ;
grid_pattern(, ,) ;
...
}
Defining the Detail Routing Grid
You specify the routing track grid for the gate array by using the tracks group inside the
array group. In the tracks group, you specify the track pattern, the track direction, and
the layers available for the associated tracks.
Note:
Define one tracks group for horizontal routing and one for vertical routing.
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Syntax
array(array_name
id
) {
...
tracks() {
layers : "layer_1", "layer_2", ..."layer_n" ;
routing_direction : vertical | horizontal ;
track_pattern(start_point
float
, num_of_tracks
float
,
space_between_tracks
float
) ;
}
}
where
start_point
A floating-point number representing the starting-point coordinate
num_of_tracks
A floating-point number representing the number of parallel tracks
space_between
A floating-point number representing the spacing between the tracks
Example
phys_library(example) {
...
resource(array) { /* gate array technology */
...
array(samplearray) {
...
tracks() {
layers : "m1", "m3" ;
routing_direction : horizontal ;
track_pattern(1, 50, 10) ;
/* 50 horizontal tracks 10 microns apart */
} /* end tracks */
tracks() {
layers : "m1", "m2" ;
routing_direction : vertical ;
track_pattern(1, 50, 10) ;
/* 50 vertical tracks 10 microns apart */
}/* end tracks */
} /* end array */
} /* end resource */
...
} /* end phys_library */
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Defining the Design Rules
Specify design rules for the technology, such as minimum spacing and width, by using the
topological_design_rules group.
This chapter includes the following sections:
•
Defining Minimum Via Spacing Rules in the Same Net
•
Defining Same-Net Minimum Wire Spacing
• Defining Same-Net Stacking Rules
•
Defining Nondefault Rules for Wiring
•
Defining Rules for Selecting Vias for Special Wiring
• Defining Rules for Generating Vias for Special Wiring
•
Defining the Generated Via Size
Defining the Design Rules
The following sections describe how you define the design rules for physical libraries.
Defining Minimum Via Spacing Rules in the Same Net
The design rule checker requires the value for the edge-to-edge minimum spacing
between vias.
Use the contact_min_spacing attribute for defining the minimum spacing between
contacts in different nets. This attribute requires the name of the two contact layers and
the spacing distance. To specify the minimum spacing between the same contact, use the
same contact layer name twice.
Syntax
topological_design_rules() {
contact_min_spacing(contact_layer1
id
,
contact_layer2
id
, spacing
float
) ;
... }
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Example
phys_library(sample) {
...
topological_design_rules() {
...
contact_min_spacing(cut01, cut12, 1) ;
...
}
...
}
Defining Same-Net Minimum Wire Spacing
You can specify the minimum wire spacing between contacts in the same net by using the
same_net_min_spacing attribute. To specify the minimum spacing between the same
contact, use the same contact layer name twice.
Syntax
topological_design_rules() {
same_net_min_spacing(layer1_name
id
, layer2_name
id
,
spacing
float
, ...) ;
...
}
Example
topological_design_rules() {
same_net_min_spacing(m1, m1, 0.4, ...) ;
same_net_min_spacing(m3, m3, 0.4, ...) ;
...
}
Defining Same-Net Stacking Rules
You can specify stacking for vias that share the same routing layer by setting the
is_stack parameter in the same_net_min_spacing attribute to TRUE.
Syntax
topological_design_rules() {
same_net_min_spacing(layer1_name
id
, layer2_name
id
,
spacing
float
, is_stack
Boolean
) ;
...
}
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Example
topological_design_rules() {
same_net_min_spacing(m1, m1, 0.4, TRUE) ;
same_net_min_spacing(m3, m3, 0.4, FALSE) ;
...
}
Defining Nondefault Rules for Wiring
For all regular wiring, you define the default rules by using either the layer group or the
via group in the resource group. You define the nondefault rules for wiring by using the
wire_rule group in the topological_design_rules group as shown here:
phys_library(sample) {
...
topological_design_rules() {
...
wire_rule(rule1) {
via(non_default_via12) {
...
}
}
}
}
You define the width, different net minimum spacing (edge-to-edge), and the wire
extension by using the layer_rule group. The width and spacing specifications override
the default values defined in the routing_layer group.
phys_library(sample) {
...
topological_design_rules() {
...
layer_rule(metal1) {
/* non default regular wiring rules for metal1 */
wire_width : 0.4 ; /* default is 0.32 */
min_spacing : 0.4 ; /* default is 0.32 */
wire_extension : 0.25 ; /* default is 0.4/2 */
} /*end layer rule */
}
}
Use the via group in the wire_rule group to define nondefault vias associated with the
routing layers. This via group is similar to the via group in the resource group except that
the is_default attribute is absent. For regular wiring, the via defined in the wire_rule
group is considered instead of the default via defined in the resource group whenever the
wire width matches the width specified in the via or layer group.
phys_library(sample) {
...
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topological_design_rules() {
...
wire_rule(rule1) {
via(non_default_via12) {
...
}
}
}
}
For nondefault regular wiring, you define the via and routing layer spacing and the
stacking rules by using the same_net_min_spacing attribute inside the wire_rule group.
This attribute overrides the default values in the same_net_min_spacing attribute inside
the topological_design_rules group.
phys_library(sample) {
...
topological_design_rules() {
...
wire_rule(rule1) {
same_net_min_spacing(m1, m1, 0.32, FALSE) ;
same_net_min_spacing(m2, m2, 0.4, FALSE) ;
same_net_min_spacing(cut01, cut01, 0.36, FALSE) ;
same_net_min_spacing(cut12, cut12, 0.36, FALSE) ;
} /* end wire rule */
} /* end design rules */
} /* end phys_library */
Use the vias attribute in the via_rule group to specify a list of vias. The router selects
the first via that satisfies the design rules.
Defining Rules for Selecting Vias for Special Wiring
The via_rule group inside a topological_design_rules group defines vias used at the
intersection of special wires in the same net.
You can specify multiple via_rule groups for a given layer pair. The rule that governs the
selection of a via_rule group is the routing wire width range. When the width of a special
wire is within the range specified, then the via rule is selected. When no via rule applies,
then the default via rule is applied. The default via rule is created when you omit the
routing wire width specification. You also specify contact overhang and metal overhang, in
both the horizontal and vertical directions, in the via_rule group. Contact overhang is the
minimum amount of metal (wire) between the contact and the via edge. Metal overhang is
at the edges of wire intersection. Figure 11 shows these relationships.
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Figure 11 Contact Overhang and Metal Overhang
Syntax
topological_design_rules() {
...
via_rule(via_rule_name
id
) {
vias : list_of_vias
id
;
routing_layer_rule(routing_layer_name
id
) {
/* one for each layer associated with the via; */
/* normally 2. */
routing_direction : value
enum
;
/* direction of the overhang */
contact_overhang : value
float
;
metal_overhang : value
float
;
min_wire_width : value
float
;
max_wire_width : value
float
;
}
}
}
Example
topological_design_rules() {
...
via_rule(default_rule_for_m1_m2) {
/* default via rule for the metal1, metal2 pair; */
/* no wire width range is specified */
vias : "via12, via23" ;
/* select via12 or via23 - whichever satisfies */
/* the design rules*/
routing_layer_rule(metal1) {
routing_direction : horizontal ;
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contact_overhang : 0.1 ;
metal_overhang : 0 ;
}
routing_layer_rule(metal2) {
routing_direction : vertical ;
contact_overhang : 0.1 ;
metal_overhang : 0 ;
}
}
...
}
Defining Rules for Generating Vias for Special Wiring
Use the via_rule_generate group to specify the rules for generating vias used at
the intersection of special wires in the same net. You define this group inside the
topological_design_rules group. viasgeneratingYou can specify multiple via_rule_generate groups
for a given layer pair.
The rule that governs the selection of a via_rule group is the routing wire width range.
When the width of the special wire is within the range specified, then the via rule is
selected. When no via rule applies, then the default via rule is applied. The default via
rule is created when you omit the routing wire width specification. Use the vias attribute
in the via_rule_generate group to specify a list of vias. The router selects the first via
that satisfies DRC. You also specify contact overhang and metal overhang, in both the
horizontal and vertical directions, in the via_rule_generate group. Contact overhang
is the minimum amount of metal (wire) between the contact and the via edge. Metal
overhang is at the edges of wire intersection.
You specify the contact layer geometry generation formula in the contact_formula group
inside the via_rule_generate group. The number of contact cuts in the generated array
is determined by the contact spacing, contact-cut geometry, and the overhang (both
contact and metal).
Syntax
topological_design_rules() {
...
via_rule_generate(via_rule_name
id
) {
routing_layer_formula(routing_layer_name
id
) {
/* one for each layer associated with the via */
/* normally 2 */
routing_direction : value
enum
;
/* direction of the overhang */
contact_overhang : value
float
;
metal_overhang : value
float
;
min_wire_width : value
float
;
max_wire_width : value
float
;
}
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contact_formula(contact_layer_name) {
rectangle(x1
float
, y1
float
, x2
float
, y2
float
) ;
/* specify more than 1 rectangle for */
/* rectilinear vias */
contact_spacing(x_spacing
float
, y_spacing
float
)
resistance : value
float
}
}
Example
phys_library(sample) {
...
resource(std_cell) { /* standard cell technology */
...
} /* end resource */
topological_design_rules() { /* design rules */
same_net_min_spacing(m1, m1, 0.32, FALSE) ;
/* minimum spacing required between 2 metal1 layers in the same net */
same_net_min_spacing(m2, m2, 0.4, FALSE) ;
/* minimum spacing required between 2 metal2 layers in the same net */
same_net_min_spacing(m3, m3, 0.4, FALSE) ;
/* minimum spacing required between 2 metal3 layers in the same net */
same_net_min_spacing(cut01, cut01, 0.36, FALSE) ;
/* minimum spacing required between 2 contact cut01 layers in the same net
*/
same_net_min_spacing(cut12, cut12, 0.36, FALSE) ;
/* minimum spacing required between 2 contact cut12 layers in the same net
*/
same_net_min_spacing(cut23, cut23, 0.36, FALSE) ;
/* minimum spacing required between 2 contact cut23 layers in the same net
*/
/* via generation rules */
via_rule_generate(default_rule_for_m1_m2) {
routing_layer_formula(metal1) {
routing_direction : horizontal ;
contact_overhang : 0.1 ;
metal_overhang : 0.0 ;
}
routing_layer_rule(metal2) {
routing_direction : vertical ;
contact_overhang : 0.1 ;
metal_overhang : 0 ;
}
contact_formula(cut12) { /* rule for generating contact cut array */
rectangle(-0.2, -0.2, 0.2, 0.2) ; /* cut shape */
contact_spacing(0.8, 0.8) ; /* center-to-center spacing */
resistance : 1.0 ; /* cut resistance */
}
} /* end via_rule_generate */
via_rule_generate(default_rule_for_m2_m3) {
routing_layer_formula(metal2) {
routing_direction : vertical ;
contact_overhang : 0.1 ;
metal_overhang : 0.0 ;
}
routing_layer_rule(metal3) {
routing_direction : horizontal ;
contact_overhang : 0.1 ;
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Defining the Design Rules
metal_overhang : 0 ;
}
contact_formula(cut23) { /* rule for generating contact cut array */
rectangle(-0.2, -0.2, 0.2, 0.2) ; /* cut shape */
contact_spacing(0.8, 0.8) ; /* center-to-center spacing */
resistance : 1.0 ; /* cut resistance */
}
} /* end via_rule_generate */
} /* end design rules */
macro(and2) {
...
} /* end macro */
} /* end phys_library */
Defining the Generated Via Size
Generated vias are a multiple of the minimum feature size. The lithographic grid
determines the minimum feature size for the technology.
Syntax
min_generated_via_size(x_size
float
, y_size
float
) ;
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A
Parasitic RC Estimation in the Physical Library
This chapter includes the following sections:
• Modeling Parasitic RC Estimation
•
Variables Used in Parasitic RC Estimation
• Equations for Parasitic RC Estimation
•
.plib Format
Modeling Parasitic RC Estimation
Figure 12 provides an overview of the measures used in the parasitic RC estimation
model.
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Modeling Parasitic RC Estimation
Figure 12 Parasitic RC Estimation Model
The following sections provide information about the variables and equations you use to
model parasitic RC estimation.
Variables Used in Parasitic RC Estimation
The following sections list and describe the routing layer and routing wire variables you
need to define in the RC estimation model.
Variables for Routing Layers
Define the following set of variables for each routing_layer group in your physical
library.
Variable Description
res_per_sq Resistance per square of a res_per_sq routing layer.
cap_per_sq Substrate capacitance per cap_per_sq square of a poly
or metal layer (CP layer).
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Variable Description
coupling_cap Coupling capacitance per unit length between parallel
wires on the same layer (CC layer).
fringe_cap Fringe (sidewall) capacitance per unit length of a
routing layer (CF layer).
edgecapacitance Total fringe capacitance per unit length of routing layer.
Specifies capacitance due to fringe, overlapping, and
coupling effect.
inductance_per_dist Inductance per unit length of a routing layer.
shrinkage Distance that wires on the layer shrinks or expands on
each side from the design to the fabricated chip. Note
that negative numbers indicate expansion and positive
number indicate shrinkage.
default_routing_width Default routing width for wires on the layer.
height Distance from the top of the substrate to the bottom of
the routing layer.
thickness Thickness of the routing layer.
plate_cap Capacitance per unit area when the first layer overlaps
the second layer. This function specifies an array of
values indexed by routing layer order (CP layer, layer).
Variables for Estimated Routing Wire Model
Define the following set of variables for each routing_wire_model group in your physical
library. Each routing_wire_model group represents a statistics-based design-specific
estimation of interconnect topology.
overlap_wire_ratio
Percentage of the wiring on the first layer that overlaps the second layer. This
function specifies all overlap_wire_ratio values in an n*(n-1) sized array, where
n is the number of routing layers. For example, the overlap_wire_ratio values
for the first routing layer (routing layer 1) are specified in overlap_wire_ratio[0]
to overlap_wire_ratio[n-2]. The values for routing layer 2 are specified in
overlap_wire_ratio[n-1] to overlap_wire_ratio[2(n-1)].
adjacent_wire_ratio
Percentage of wiring on the layer that runs adjacent to and has minimum
spacing from wiring on the same layer. This function specifies percentage values
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of adjacent wiring for all routing layers. For example, two parallel adjacent wires
with the same length would have an adjacent_wire_ratio of 50 percent.
wire_ratio_x
Percentage of total wiring in the horizontal direction that you estimate to be on
each layer. The function carries an array of floating-point numbers, following
the order of routing layers. That is, there are three floating-point numbers in the
array if there are three routing layers. These numbers should add up to 1.00.
wire_ratio_y
Percentage of total wiring in the vertical direction that you estimate to be on
each layer. The function carries an array of floating-point numbers, following
the order of routing layers. That is, there are three floating point numbers in the
array if there are three routing layers. And these numbers should add up to 1.00.
wire_length_x, wire_length_y
Estimated wire lengths in horizontal and vertical direction for a net.
Equations for Parasitic RC Estimation
Parasitic calculation is based on your estimates of routing topology prior to detail routing.
The following sections describe how to determine those estimates.
Capacitance per Unit Length for a Layer
Use the following equations to estimate capacitance per unit length for a given layer.
cap_per_dist
layer
= W * cap_per_area
layer
+ fringe_cap
layer
+
coupling_cap_per_dist
layer
where
W = (default_wire_width | actual_wire_width) - shrinkage
cap_per_area
layer
= 1 - SUM_overlap_wire_ratio_under
layer
*
cap_per_sq
layer
+
SUM
i=other_layer
[overlap_wire_ratio
j,layer
]
* plate_cap
layer,i
where
SUM_overlap_wire_ratio_under
layer
=
SUM
j=layer_underneath
[overlap_wire_ratio
j,layer
]
Note:
This equation represents the sum of all the overlap_wire_ratio values
between the current layer and each layer underneath the current layer.
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coupling_cap_per_dist
layer
=
2 * adjacent_wire_ratio
layer
* coupling_cap
layer
Resistance and Capacitance for Each Routing Direction
Use the following equations to estimate capacitance and resistance values based on
orientational routing wire ratios.
capacitance x = cap_per_dist x * wire_length_x
capacitance y = cap_per_dist y * wire_length_y
resistance x = res_per_sq x * wire_length x / width x
resistance y = res_per_sq y * wire_length y / width y
where
cap_per_dist x = SUM[wire_ratio_x layer * cap_per_dist layer]
cap_per_dist y = SUM[wire_ratio_y layer * cap_per_dist layer]
res_per_sq x = SUM[ wire_ratio_x layer * res_per_sq layer ]
res_per_sq y = SUM[ wire_ratio_y layer * res_per_sq layer ]
width x = SUM[ wire_ratio_x layer * W layer ]
width y = SUM[ wire_ratio_y layer * W layer ]
.plib Format
To provide layer parasitics for RC estimation based on the equations shown in this section,
define them in the following .plib format.
physical_library(name){
...
resistance_lut_template (template_name
id
) {
variable_1: routing_width | routing_spacing ;
variable_2: routing_width | routing_spacing ;
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
}
resource(technology) {
field_oxide_thickness : float ;
field_oxide_permitivity : float ;
...
routing_layer(layer_name
id
) {
cap_multiplier : float ;
cap_per_sq : float ;
coupling_cap : float ;
default_routing_width : float ;
edgecapacitance : float ;
fringe_cap : float ;
height : float ;
inductance_per_dist : float ;
min_area : float ;
offset : float ;
oxide_permittivity : float ;
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oxide_thickness : float ;
pitch : float ;
ranged_spacing(float, ..., float) ;
res_per_sq : float ;
routing_direction : vertical | horizontal ;
shrinkage : float ;
spacing : float ;
thickness : float ;
wire_extension : float ;
lateral_oxide (float, float) ;
resistance_table (template_name
id
) {
index_1 ("float, float, float, ...") ;
index_2 ("float, float, float, ...") ;
values ("float, float, float, ...") :
}
} /* end routing_layer */
plate_cap(value, value, value, value, value, ...) ;
/* capacitance between wires on lower and upper layer */
/* MUST BE DEFINED BEFORE ANY routing_wire_model GROUP DEFINITION */
/* AND AFTER ALL *_layer() DEFINITIONS */
routing_wire_model(name) {
/* predefined routing wire ratio model for RC estimation */
overlap_wire_ratio(value, value, value, value, value, ...) ;
/* overlapping wiring percentage between wires on different layers. */
/* Value between 0 and 100.0 */
adjacent_wire_ratio(value, value, value, ...) ;
/* Adjacent wire percentage between wires on same layers. */
/* Value between 0.0 and 100.0 */
wire_ratio_x(value, value, value, ...) ;
/* x wiring percentage on each routing layer. */
/* Value between 0.0 and 100.0 */
wire_ratio_y(value, value, value, ...) ;
/* y wiring percentage on each routing layer. */
/* Value between 0.0 and 100.0 */
wire_length_x : float ;
/* estimated length for horizontal wire segment */
wire_length_y : float ;
/* estimated length for vertical wire segment */
}
}
topological_design_rules() {
...
default_via_generate( ) {
via_routing_layer ( ) {
end_of_line_overhang : ;
overhang ( ) :
}
via_contact_layer ( ) {
end_of_line_overhang : ;
overhang ( ) :
rectangle(float, float, float, float) ;
resistance : float ;
}
}
}
process_resource () {
process_routing_layer () {
res_per_sq : float;
cap_per_sq : float ;
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coupling_cap : float ;
/* coupling effect between parallel wires on same layer */
fringe_cap : float ; /* sidewall capacitance per unit length */
edgecapacitance: float ; /* lumped fringe capacitance */
inductance_per_dist : float ;
shrinkage : float ; /* delta width */
default_routing_width : float; /* width */
height : float ; /* height from substrate */
thickness : float ; /* interconnect thickness */
lateral_oxide_thickness : float ;
oxide_thickness : float ;
}
process_via () {
.resistance : float ;
}
process_array () {
default_capacitance : float ;
}
process_wire_rule () {
process_via () {
resistance : float ;
}
}
}
macro() {
...
}
}
The .plib file that contains the wire_ratio model is as follows:
resource (technology) {
routing_wire_model(name) {
overlap_wire_ratio(value, value, value, ...);
adjacent_wire_ratio(value, value, value, ...);
wire_ratio_x(value, value, value, ...);
wire_ratio_y(value, value, value, ...);
wire_length_x : float;
wire_length_y : float;
}
}
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